I am sick of this argument: lets not forget the relative consequences of a bike not stopping vs a car not stopping:
If a car rolls through a stop sign and hits a bicyclist, pedestrian or another car, There will likely be severe injurys. The car driver will however likely be fine (unless it is another car involved).

If a bike does the same the operator of the cycle may be hurt (or killed - I am not advocating that we be allowed to roll through stop-signs willy-nilly), but the damages to the other party will likely be pretty minimal.

I think that this discussion too often ignores this fact.

Wouldn't it make sense to have penalties for these sort of infractions be incremented based upon the gross weight of the offending vehicle? Perhaps with some minumum fine as well?