The problem is that Russia will usually have a force consisting mostly of infantry, which are weak when attacking and will not force nearly as many Germans to stay behind to defend the counterattack as they would have killed in defense. Your example of killing less than half of the IPCs that the Germans will kill means the Germans are attacking with such overwhelming force (maybe 3:1 in IPC value) that the game is likely lost anyway.
In G1 Barbarossa games I’ve seen - if Russia doesn’t adventure too much, and if UK/US are able to get a few (six or seven) fighters to Moscow, Germany should win with a few armor remaining and all their airforce. To me, this is a good exchange, IF the UK was rooted in to the Middle East and has been producing infantry for the last 4 or 5 turns.
If not… Germany will turn south and crunch the center of the board. Game over.
a losing battle does not become better by standing, there has to be a very narrow margin if standing with 7 extra inf and dying is better than retreating. For one thing, He might relocate his airforce allowing you back into moscow.
I think you seriously underestimate the strength of infantry on attack, if you have two inf stacks, then the attacking stack need to be 1.41 times the defending stack for it to be an even fight. with some artillery and planes, you should be quite formidable on the attack. Once you realise you will have to retreat the next round, you could always do a 100% art build if you have too many infs.
You will almost always be able to bind up more german resources by leaving than you would kill by standing.
by all means if he has a 55% shot at winning, sure you can stand, but when he has 70% chance of winning, and 60% chance of not losing planes, then you will always lose more IPCs compared to what he will lose.
