Because for that game, it seemed that 1:subs still were screwing with me 2: I had made many attempts to invade, but failed miserably every time
The key is sustainability – you have to set up a “chain” of transports that can get troops into Europe EVERY TURN. It takes a while to build that chain, but once you do, it’s the kiss of death for the Krauts.
As for subs, DDs and bombers are key. And Germany shouldn’t be buying that many subs after about turn 3 or she will run short on land units (at least, if you are taking advantage of the rule that allows you to move British and American stuff the Russia and have it converted to Russian pieces. That’s a BIG headache for Germany to overcome).
You have to follow history atleast slightly. Pull all russia forces back to your cities and if that wont hold think of puting every man in moscow. That is an incredible amount of defense. It is also key that america and the UK take the sea and put pressure on Germany so they cant devote all their forces and money to killing russia. They might even want to consider shiping planes over that russia can take control of. 8 planes in moscow with a role of 4 or less is incredible defense against tanks. If the Germans are going after russia full force just pull back to moscow and let US and UK take the covoys back, supply troops, and put pressure on Germany. If Germany always wins it is because the people playing US and UK suck at the game.