1 well microed kubel isn't going to stop 5 con squads back up by 4 rifle squads, Allies having the early game advantage is pretty well documented. Honestly, it's stupid that each side has a distinct advantage at certain points in the game rather than all factions scaling equally over time.
Con spam and Rifle spam in 4's is very, very deadly. The advantage allies have in getting better infantry units out the door faster early game is amplified, then if you add in the Ostheers weakness to USF and OKW's poor early starting units it's quite easy to lock down most of the map as allies in the first 5-8 minutes.
Wow you make it sound almost like allies have a chance in 4v4.
You are correct 1 kubel won't stop 9 squads of inf, expect that even if all 4 players do that you are still at minute 3, and you completely ignore the fact that there are 3 other German players.
The hard hitting allied inf are less impressive in large games, actually, because their window of use is shorter, and the Germans can actually tech to better units quickly.
Also you can't lock down most of the map by minute 8 even if you can the OKW players have bases up you are going to pound your head against. And they lose nothing by having 1 person go stuka to nullify your support weapons.
Con spam and Rifle spam is just about all the allies have and its really not good.
Seriously though you make it sound like allies have the advantage in large games, and they are completely out matched from the word go.