Originally Posted by
travelinhobo
Attention to all those who street/road bicycle in the U.S.:
When bicycling on the sidewalk parallel to a busy road, I have figured out how to safely cross the intersecting street to the other side (when I have the right to do so) so that an idiot driver who wants to turn right doesn't try to beat me or miss my presence. When you are closing in on the corner, within 20 feet or so, stick your left arm out just as you do if you were signaling to turn. Keep it out until you're on the street, crossing over. I started doing this about a year ago and it works spectacularly well keeping idiot drivers from turning as I'm crossing. Of all the times I've done it, only once has a driver chosen to ignore me. (Whether drivers use caution wondering what I'm doing or believe I'm about to take a sharp left into the road, I do not know. Nor do I care. It works and that's all I'm concerned about.)
Yes, yes, I know. It is illegal 96% of the time to ride on the sidewalk. And 97% of the time, I ride on the road. However, there are times when cycling on the sidewalk (being respectful and mindful of others) is safer, saner and/or required. So, don't try to crap on me helping others.
Good to meet you in person a couple weeks ago. Hope your travels go well.
Ignoring the Sidewalk Wars and getting back to the actual original statement:
Rider is going down sidewalk, and extends left hand approaching an intersection.
Other road users: "That rider must be planning to turn left. But they are to the far right. They might turn across my path." So the more-responsible road users slow so they can increase space or have more reaction time to the expected left turn.
Turn does not occur. Bicyclist continues straight. Other road users may be puzzled, irritated, or have no reaction at all, but no apparent hostility and life goes on.
I'm personally not usually a fan of signalling turns that aren't planned to be made, but let's leave that aside. What are the likely results of this behavior?
The first one noted by the OP is that other traffic slows and seems more prepared to yield. Typically a good thing.
But what will the other drivers think when they encounter the next rider signalling a left turn? Around here, bicyclists using hand signals (of a family-approved type, that is) are not common. If a road user sees 10 left turn signals by bicyclists and 9 of the riders turns left, then the signal retains some credibility. If road users see a lot of signaling without turns, then you could have a situation where road users start ignoring the signals of others, like someone who has a notch in their hearing matching up with the click of the turn signal rolling merrily along with the turn signal flashing away even though they've been going straight for miles (my wife really doesn't like it when this hypothetically occurs while I am driving). Also, if they see the same rider signalling and not turning on a repeated basis, like for example someone with a distinctive full touring load on a bright red bike, they may start ignoring all signals from that bike, which might eventually be bad.
So, in summary: signals from one or two people that send mixed messages can get desired behavior from others, but if more people start doing it, it could lead to problems. That's my roadway human factors 2¢.