I might be wrong on the Ki84 and confusing it with compression. I only remember making the same mental note as the mossie, thinking about making a fourth control mode with manual trim mapped to the joystick so I could pull more than combat trim allowed. It's not hard to test for yourself. Fly with combat trim and try pulling +G into a stall. If it doesn't happen, try trimming it some more. If combat trim is limiting the 84 as it does the mossie, you'll be able to stall it out when trimmed but not when CT'd.