RE: Downwind Turns!!
The reason the plane will balloon or drop the nose is one of two reasons
1: ballon or drop the nose due to too little or too much elevator given for the bank angle
2: nose suddenly drops due to exceeding the critical AOA in high banked turns even at high speed and throttle settings.
Your explanation sounds like what happens with a hovercraft or airboat. Short of a 3D aircraft in the most extreme manuevers planes can't turn like that.