Quick Commands aside -- issuing "March" doesn't eliminate the bunching up problem, at least not on roads hemmed in by narrow spaces, in villages or in forests. Especially in forests, where as the German player you really need to be able to give your vehicles commands to remain on the roads -- this bunching up, even with March order, is really really frustrating --
I find that with vehicles it is best to avoid villages or forests all together.You may be able to get 1 or 2 vehicles to manuever through these obsticals with out immobilizing them or bunching up.But,with larger units you are just asking for trouble.