Shortening the front via counter-operations and phased withdrawals is common sense, though?
You say it is common sense, but actually putting the into action is another thing entirely. Putting common sense to practice is what is significant. The Soviets and Allies never demonstrated a similar ability to withdraw while keeping their combat effectiveness intact during the early years by comparison. The British and French position at Dunkirk bordered on hilarity and the Soviet Union was by most accounts in complete disarray when on the defense for the first time in 1941.
At any rate we can now make some excellent tactical and strategic decisions about a war that was waged 70 years ago, now that we had all or most of the facts from both sides. The parties at that time suffice it to say did not have the luxury and it can be reasoned that many of the decisions made at the time were justified by what either side knew/believed at the time. If you won, you were the brilliant gambler, if you lost you were hopelessly doomed all along, or so the histories go.