Is Meth the Best Way to Conquer Russia?

During Barbarossa, German soldiers conquered more territory than any army ever. The problem with Russia though is that it's very big and the Russians just kept retreating. So by the time they reached the point where it's like, well, we even on meth, we can't keep taking meth and not sleeping,. We're all crashing. And a really bad hangover is being in the middle of Russia. Ooh, you do not want to be coming down from a three-day meth bender under heavy fire.