[RoughDobermann]

But, if you piddle along at 15 mph, we will have problems

Why?

[Skooz]

Why?

I put it in the next sentence: Slowing down traffic and presenting a movable obstacle is a traffic hazard.

[Geritol]

Why not go 30 or 45 miles under the speed limit? Cause it is not safe. For anyone on the road.

Many states have minimum speed laws for cars for most roads that is set to keep the closing velocity down in the reasonable numbers. If a bike is supposed to folow all the laws that a vehicle is supposed to follow, I could imagine that this minimum speed would also be a good idea, but not real feasible for the biker. If the road has a speed limit that is totally unachievable for the bike, the bike should try very hard to stay out of the way. Forcing the cars behind the bike to go at it's speed is not at all safe, especially for the cars at the rear of the line