It was only a maneuver they survived the second time was because they literally packed up and moved everything they could, brick by brick and man by man, into the interior. Wasn't a whole lot left to scorch in the end. Even so it hurt them for decades to come. I dunno, a lot of people look at Stalin being ruthless and think it was him being Machiavellian because in the end he did win, but he was a pretty awful military planner who just so happened to have at his disposal the most powerful production center in the hemisphere.