This doesn't sound right. Don't know about in-game flight characteristics, cause I haven't flown in a while, but in real life, if a pilot were following a con with near equal or superior energy into the vertical, popping his flaps was NOT something he would want to do.
Deploying the flaps would not only rob him of his energy, but also blank the ailerons, robbing them of control authority. I don't care how "stable" the Corsair's flaps made it in level flight, vertical control would be another matter altogether. When stall speed was reached he would either go into a tail slide, with no control authority whatsoever, or he would fall off on one wing, nose down and helpless.
In all probability, your opponent had more energy than you realized and bled you dry of your own. So, you stalled first, and he latched onto your tail.