What do you mean by Pz.kmfw. IV being detrimental?
Didn't word it properly though. Sorry.
I meant that it had its own share of problems that sometimes had parts going wonky as well issues of the old iterations having breakdowns. afaik old Pz IV's were blasted easily by T-34's packing their F-34's until on model E and F2 that they started to be gritty enough to be one of the tanks that can shrug off 76mm rounds in a ranged firefight and not on close range slugfests.