Assumption: If the speed limit on a given road is 55 miles per hour, then that speed limit is the speed — give or take a few miles per hour — that is reasonable to drive under perfect conditions.  Question:  Is it reasonable to expect folks to drive less than 55 mph under less than perfect conditions?  Another question:  Is it reasonable to expect folks to drive substantially less than the posted speed limit when conditions are almost as bad as they could possibly be — to wit, a half inch sheet ice covering the road?

 It is interesting to me that if visibility is less than 50 feet or so, folks tend to drive quite slow, but when icy conditions impair their stopping and steering ability, they do not slow down.  But the effect is the same.  You can’t stop or steer in time to miss your target. 

 I suspect that if folks tested their traction more often on slick roads, they would slow down more.

 And here is another thing.  While driving in heavy snow yesterday, we had probably 40 cars pass us.  38 out of 40 had Illinois plates.  Interesting?  I think so.