@ mrodgers (in reference to post directly above)
Actually I've found the exact opposite to be true. I used to be a white line hugger and I am very lucky to have survived that period of my life. I had so many close call of passes where the edge of the car was literally within inches or actually literally brushed against me because the drivers refused to slow down and hardly even moved over in the lane much less swerved. I've actually had much better results from riding "IN the road" and "taking the lane" riding VC style because drivers actually bother to take their foot of the gas and maybe even hit the brake and when they pass swing wide and do a full vehicular lane change pass.
As to deer, even in all my years of driving 2-5 ton short truck and car driving I have never hit one of them, several people I have taught how to drive correctly have also never hit one of them. If you hit a deer the vast majority of the time it is because you were driving too fast for conditions namely your ability to see far enough ahead to be able to stop in time if necessary. You know those yellow curve signs that say like 35-mph for around the curve those actually are there for a reason and if you actually slow down for the curve to that speed even if there is a deer or a stalled car or a cyclist or a pedestrian or a downed tree or . . . in the road you will be able to stop in time to avoid hitting. If instead you be an idiot speed demon and drive faster then your visibility ahead allows you will indeed hit stuff that is right in front of you.
Also, realize a bike is moving down the road in the same direction ahead of you and that makes a huge difference in closing speed. Rarely does a deer run down the road at 20-25 mph ahead of you which shaves your suggested 55-mph speed down to a closing speed of 30-35mph because the deer is moving too. That makes a huge difference (and is one of the reasons you ride a bike with traffic not against it). Granted hills do slow me down some as do headwinds but that is by no means an uncommon speed for me especially since if I'm in the main traffic lane I make "best effort" to keep my speed up because when cars are going faster then you every bit of speed you can muster makes you safer and reduces the closing speed that they are coming up behind you.
Yes, I do understand what you are saying and that most people drive like speed demon idiots and one must recognize that fact and prepare for it to stay alive. For me, having them see me right in the middle of the road has had much better results with them actually using their brakes and actually trying to get over allowing me to also get over the other way (could be either way have to watch them in the mirror and go whichever way they don't).
Hug the white line and they don't even take their foot off the gas or even try to move over within the lane much less change lanes to pass.
Long story short, I've had less close calls and less injuries since I started taking the lane instead of white line hugging. Not the other way around, it defies "common misconception logic" but it has been my experience.
Yah, I realize that tomorrow or even tonight (got to get my butt in gear and take a 15 mile ride into town here shortly) could be the time that one motorist decides to just ram into me and that will be curtains for me. But everything I've learned from near daily experience on the roads up here over the last couple decades has taught me that once a road gets narrow enough and there isn't a ride-able shoulder edge it's actually riskier to hug the white line then to "take the lane". I know, its contrary to "haven't tried that but that's how I think it would work" logic but actually doing at least in my area on the roads up here that's what my actual real world experience has been.
And since I'm about to head out. When it comes to after dark, I will say that how good your light set-up determines whether you almost get killed (I only have personal direct knowledge as to the almost get killed part, knowledge of the actually get killed part is only second or third hand) or makes motorists usually notice you even sooner, slow down even more, and pass even wider then daylight depending on how you do them.
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As to traffic density on those roads. I wish that genec was right and that they were all low traffic. It is true that the traffic does vary by the day and by the hour (some are hell on the weekdays and quite on the weekend and some are hell on the weekend and quieter during the week and also by time of day, etc . . .) and some are lower traffic then others but I really won't consider any of them to have low enough traffic volume to say "don't worry about it there isn't enough traffic on those words to worry about".
I'll give a short run down of the roads in question going from the worst to the best (every google road-view link I posted above is on one of these):
~ US-93 North of Whitefish, MT all the way up to the Can. border = Heavy traffic most of the week and day and with terrible narrow sections = two pictures of this one namely the corner at Striker, MT and the railway overpass both of which are death traps. Speeds are 60+ with heavy boarder traffic (busiest border crossing on the Montana line). This is a major artery, this is by no means local yo-you traffic only. This road desperately needs to have consistently 4' wide shoulder edges added to it to make it safer for all users !!! I would gladly shoulder edge ride to the right of the white line on this road if given the opportunity.
~ US-2 from one end of the state to the other E. to W. = a major long distance artery. Spots of it do have a nice wide shoulder edge and I gladly use it but the majority of it is terrible and everything west of Browning, MT all the way into Idaho where it is narrowest is often where it is most heavily traveled !!! Local traffic does make up a good segment on this road (lots of long distance motorist commuters use it) but its most certainly still a major artery for cross state private and commercial transit. Again my suggestion for this road is once again the addition of consistently 4' wide shoulder edges to make it safer for all users !!! Once again I would gladly use them.
~ MT-35 = actually pretty nice from Kalispell to the offset double T intersection with MT-82/MT-83 with reasonable shoulder edge width the vast majority of that stretch. But from that intersection south to Polson its terribly narrow as it winds around the east side of Flathead lake and except for some off hours has dense traffic consisting of a bunch of speed demons trying to go as fast as they can on it using it as a shortcut compared to going around the other side of the lake. Thankfully there is also a large contingent of commercial truckers that use it for the same reason and they actually go the speed limit on that section (never higher then 50-mph) and act as a buffer to block up and slow down the 4-wheel maniacs that try to do 70+ on "their shortcut" and as a result there is a huge animosity towards truckers that use that road and there have been many political attempts to get them banned from using it which thankfully have been unsuccessful. For this reason I try to use that road when I know the truck traffic on it will be the heaviest and so far almost without exception the truckers have always treated me well and have served as a sort of shield that has protected me from the 4-wheel speed demon maniacs. Basically I will ride VC "taking the lane" in relative peace until a big truck with a whole wall of 4-wheel slime packed in behind it like sardines for a mile comes up behind me and the truck will slow down and stay behind me often putting on their brakes way back behind me and I will look for a drive way or other such to pull out into and when found do so. The big truck will then proceed along with the mile long column of backed up impatient and irate 4-wheel maniacs and after that big long train goes by I get back on the road and I can usually make at least another mile with only the occasional lone 4-wheel maniac trying to pass me and eventually the next big truck with a train of other cars and trucks backed up behind it will catch up with me and I do the same thing over again pulling off and letting the train pass and getting a breather break and then having a relatively clear stretch to use before the next big truck catches up with a mile long train backed up behind it. Since the same kind of traffic pattern is happening in both directions those gaps between those long dense road trains with a truck going the speed limit in front in the oncoming lane allow the lone 4-wheels I encounter in the gaps the opportunity to pass safely and I do hold my line and make them wait if there is a road train in the oncoming. If I wasn't able to use that technique on that road it would probably be the worst one of them all. The road desperately needs once again 4' shoulder edges added. But the shoulder edges shouldn't be any wider then that and maybe even a little narrower down to as narrow as 3' or so and the lanes should be kept narrow and there should be a sharp preferably steep edge with no gravel transition at the edge of the paved shoulders. Otherwise the maniac 4-wheel speed demons are going to try to use the shoulder edge to pass the trucks on the right side which could be really nasty for cyclists riding on such a shoulder edge.
~ MT-82 = fairly heavy regular rush hours of local traffic since its a major connection and "the shortcut". It does have ride-able (but barely) shoulder edges from US-93 east to the bridge. The bridge itself is terrible for cyclists (and even motorists who occasionally clip each others sides across the middle line). In addition as what I consider a horrendously vicious and prejudiced oversight there is absolutely zero accommodation for pedestrians on that bridge. If you want to walk across that bridge you either have to either walk the rail on one side like a freaking circus performer or walk in the 60+ mph traffic lanes. Cyclists because we can take the lane and pedal like mad actually have it pretty good on that bridge compared to what anyone wishing to cross on foot faces. East of the bridge to the intersection with MT-35 its narrow windy high speed with pretty much not a ride-able shoulder edge. The changes that need to be made for that are at bare minimum to put 35-mph or lower speed limit for the bridge and enforce it for everyone's safety !!! Preferably with flashing yellow lights on both ends of the bridge with big signs "Extreme caution. Narrow bridge, go slow across bridge, many accidents already, some FATAL !!!" that is justified just for motorist safety alone. Adding a small lightweight pedestrian/cyclist walkway onto each side of the existing bridge would probably be the most economical solution compared to replacing the whole bridge with a wider one and would not over-stress the existing bridge structure. And then widen the shoulder edges a little west of the bridge and put in decent width shoulder edges east of the bridge and that would basically "fix" that problem along with dealing with the most serious issue of that bridge itself.
~ MT-83 = the highway that runs the length of the Swan River valley and is one of the most beautiful lush and scenic areas in the entire state. During the summer months tourist traffic on this highway is very high along with local traffic and it also serves as a short-cut that can shave nearly a 100 miles off of some trips between different parts of the state. There are some spots that do have ride-able shoulder edges but most of it does not. You will often see touring cyclists on this highway and several of them have been killed on it by motorists who often were going too fast for conditions and/or looking at the beautiful scenery and not paying attention to the road. I'm not usually a fan of separated side-paths but for this highway I think it would be the ideal solution for everyone. Especially because there are no major intersections with major cross roads so that danger is limited to only small local access roads and driveways and would certainly be the lowest risk compared to on-roadway accommodations. For this road the usual decent width and condition paved shoulder edge accommodation I usually prefer on most high speed highways I do not believe would be sufficient because you would still have a high risk of motorists paying more attention to the beautiful scenery instead of the road wandering into the shoulder edge and hitting you.
~ MT-28, MT-141, MT-200, US-12, and US-93 south of Missoula = all pretty much not too heavy traffic with the occasional local rush hour of commuters. They are generally as genec suggests only it should be made clear they are not just "local only" they are popular for travel across the state for both private and commercial traffic and are indeed arterial roadways just probably not as dense of traffic as in many other more populous states or other more heavily traveled roads in the state like all of US-93 north of Missoula.
~ MT-206 = the road that best fits genec's local yo-yos description and that is pretty much exactly what it is almost without exception.
~ Route-271 (Helmville Road) = also fits the bill with the exception that it is a highly popular shortcut to cut back and forth between I-90 and the arterial highways to the north of MT-141, MT-200, and even ultimately MT-83 and and is used by just as much if not more speed demon nuts fresh off of the interstate "taking a shortcut" and jumping up to a good access point to the northern arterial state highways. Motorists going the other direction itchy to get on the interstate aren't too fun either.
~ US-93 south from Whitefish all the way down to Missoula = actually excellent to fairly good in many areas for a cyclist to ride on the shoulder edge. Unfortunately it is one of the busiest arterial routes in that whole section of the state so where it does get narrow (as I posted one picture of) it can get pretty nasty because of the massive high speed traffic volume and believe me I know those spots very well since I travel that road many, many, many times a year across that entire length from Missoula in the south up to the whole northern Flathead valley where Kalispell is the dominant town. If they would just fix those bad occasional bad spots it would make life better and safer for everyone especially on such an major arterial roadway that is the dominant transportation route for that entire upper northwest section of the state. Once again on such high speed highways consistently 4' wide shoulder edges make it safer for all users !!! and are the only accommodation that I personally desire on such roadways as a cyclist and are my preferred accommodation.
Just because a roadway doesn't have shoulder edges for me to ride that way though doesn't mean I'm not going to ride it or that I will submit and accept vicious deliberate harassment and attacks against my RIGHT to travel on them by bicycle by both aggressive motorists and law enforcement. I will not surrender my rights to acts of terrorism and those who perpetrate them !!!