@insightful, which half of your Insight do we keep off the road? 8 P
With all respect, @Bing, it’s awful hard to use a bicycle as a mode of transportation (as opposed to “sporting goods equipment”) without using the roads. I’m all for (well designed) bike lanes (provided they don’t take roads away from cars, like Pittsburgh’s silly Mayor has been doing)–but, it’s unlikely there’s a bike lane running to every errand-stop on my list. A decent cyclist hits 15-20 MPH on the flats, and it’s just not safe for pedestrians to have to dodge somebody moving that fast on the sidewalk. Paved shoulders (if available) are nice…but they aren’t designated roadways, and therefore tend to pile up with broken glass, metal bits, and other stuff that CAN make SOME of them unsafe, in a way that might not be obvious to a non cyclist. (Heck, one road I cycled down had storm sewer grates with the slots lined up PARALLEL to traffic flow! 
)
Most serious cyclists cruise in the upper teens, and prefer roads limited to 25-35 at a max. It shouldn’t be too hard to avoid somebody when the speed differentials are modest–it’s certainly not a problem for ME, when I’m the motorist, and I drive a pretty big pickup! Trust me, if you see one of us out on a road with a higher limit than that, it’s because there was NO OTHER way from point a to point b!
In the area where I live it’s simply impossible to ride without traversing two lane roads with zero shoulders. For those that don’t ride, understand that even a modest road ride can typically be from 25 to 50 miles, and it will all be on secondary roads. It’s impossible where I am to go that far on secondary roads and always have nice shoulders.
We all need to drive and ride with consideration towards those we share the roads with. Oh, if only that were the norm.
For the record, that’s one of the reasons I loved mountain biking so much. I got really sick of fighting the cars and sucking in the output of their tailpipes… especially the diesel exhausts. I found mountain biking to be far more relaxing, clean, and safe… Trees and squirrels don’t get road rage.
...which half of your Insight do we keep off the road?
The half that plugs in…
;-]