ORIGINAL: Ktonos
Regarding massed air; When an air unit destroys an army unit it doesn't mean that a few hundred bombers managed to kill 40-60 thousand soldiers -the personnel of several divisions- merely that they managed to destroy these divisions's function to fight. If the unit was in supply these men are supposed to have withdrawn back to the reserves. If a player manages to bring 4 extra HQs in the mountains of Algeria or the deserts of Libya, this translates as an enormous effort to keep up with the logistical problems of 2000-3000 warplanes.
I totally agree.
What the Russians did in Operation August Storm to the Japanese comes to mind. 2-3000 aircraft and support transported over thousands of miles, using a single track and in complete secrecy. So there is a precedent for accomplishing such a task.
It should be rare and very costly to be sure, but possible.