I have, for the last 18 years, lived in various Canadian cities (Halifax, Montreal, Ottawa) and have commuted from medium to high density residential areas through or into the respective downtowns. I am a dedicated vehicular cyclist and conscientiously follow the traffic laws of my jurisdiction. I have six bikes: a mid 1980's Norco touring bike which I use as my longer range commuter and foul weather training bike; a 1991 Cannondale road racing bike, mostly for fitness and recreation; a 2005 Bianchi Pista track bike, mostly for fitness and recreation; an old Specialized mountain bike retrofitted with SRAAM Super 7 rear hub/coaster brake for serious winter riding; a European style city-bike built locally in Ottawa with Shimano Nexxus 7 speed rear hub and a Nexxus front hub generator; and a Burley Django recumbent. I purchased the Burley four days ago because of back problems so it may become my only bike soon.
If the commute is short enough that I can wear street clothing/office wear I will use the city bike with a shoulder bag, otherwise I use the touring bike with whatever combination of panniers is appropriate.
I extend most of my commutes, if time permits, on the ride home so that I can get an extra 10 -20 km ride out of the deal.
I can honestly say that I have never had more than one "close call" every year or two and I believe that, if I take the same route at the same time daily, after a few weeks, the motorists on that route eventually recognize me as a cyclist who obeys the rules of the road and they give me space and respect. I always take the lane at intersections, behind the last car to stop, and I never get any hassles. I also always use the correct destination positioning and, in situations in which the lane is either straight through or right turn and I am at the stop line I position myself such that right turning vehicles can turn right. When the light changes I quickly slide off to the ride side of the road as I ride out. All of this seems to work well for me.