The biggest problem is with the rules involving tank combat. A tank with a bow, coax, aa machine gun along with a MA could conceivably change its VCA five times (including intensive fire if allowed) as it is approached by the enemy tanks. So a Pz V could kill two approaching tanks and deny three more a flank or rear shot.
In the case of JgPz V, StuG III, etc., with one MG and its MA, it can still flop around like grounded salmon three times to deny flank or rear shots with a potential kill of two targets and blocking a third. The attacker can mitigate this somewhat but a machine gun should not be able to be used as a means to change VCA unless it has the ability to do damage the target, be it a TK# or the possibility to shock/Stun the crew.
Design for effect has its uses in smoothing out a rule but in so doing creates a number of abuses that make no sense.