In confined areas such as France, weak units work as speed bumps, due to EZOC behind the front line.
Be aware of a design effect:
Setting up weak units as speed bumps in Soviet has the opposite effect. There will be no "Napoleonic" long distance strategy to rely on.
Badly placed speed bumps may increase panzer movement by 100% due to exploitation and move after attack.
Check CRT before placing a weak unit. Plan for worst case. If you cannot catch the panzer in EZOC after initial attack, do not place it.
Yes - you need losses to get the juicy 8-12 units nasty surprises later, but do not let Germany gain movement on your losses.
Do not sacrifice HQ for no reason at the front. You may need them to build new units on.