Germans flew high to keep from taking main gun shots from T-34's on the eastern front,,, or was it the other way around? anyway there is another thread devoted to this and links to documents disproving the myth that it couldn't be done!
now weather it was done or not is a different story, and yes the coordination between commander and gunner would have to be almost telepathic, but many in game fly strait and level right down the barrel of a tank and then blow steam because they got killed? if I go to the gunner position and it is full of b-17,,, all i have to do is pull the trigger!
I can hit a moving tank at 4 k out on a hillside,,, why wouldn't I be able to hit a low flying, unwary pilot?