maybe this belongs in A&S, but I am more interested in what commuters think.
I commute ~400 miles per month into downtown Boston. we have here a hodgepodge of commuting infrastructure including multi-use paths, right-hand door-zone bike lanes, left-hand bike lanes, cycletracks, and ... sharrows.
Sharrows I don't understand. They seem like a waste of paint. In the 8 months I've been commuting, I can't say that I've ever noticed a motorist doing anything different because there was a sharrow in the road.
Bike lanes, by comparison, definitely have an effect. Cars stay out of the lane (for the most part) and give me space, even when I hug the left-hand side of the bike lane to avoid getting doored.
I've been on so many sharrowed roads where I get honked at, something that has never happened where there is a bike lane. I of course understand the benefits of "taking the lane" and do so when advisable, but a sharrow doesn't make me any more confident in my ability to do so.
The difference I think is that a bike lane stripe is a constant reminder that a motorist needs to leave room for a cyclist, whereas a sharrow is easy to miss. even this oft-touted SF study (http://www.industrializedcyclist.com/SFsharrows.pdf) admits that most motorists did not notice the markings. this certainly squares with my experience.
of course I understand the risks of DZBLs when people ride on the right-hand side of the lane, and I also know that every street cannot accommodate a bike lane. I just don't see the point of painting sharrows in those instances.
has anyone had more positive experiences with sharrows?