While this thread is not the place for the argument of torque vs horsepower, I can only state that torque is a measurement of rotational force against a fixed object, horsepower is a measurement of how quickly torque is produced.
Transmissions could care less how much "Horsepower" you have, it only knows/cares about the rotational force used coming from engine("INPUT FORCE") vs rotational resistance from drivetrain required to move vehicle weight(mass) at specified thrust(G-force). If the transmission "See's" more force coming in than what it's able to pass thru to driveshaft it will fail in it's "Capacity Strength" resulting in broken parts, if a clutch or band is burning it's material it is because that it does not have adequate clamping force(Line pressure to piston/servo), if converter is slipping excessively(wrong stall speed/not locking up), the working fluid will overheat and lose it's ability to lubricate(250 degrees and up), pretty much wasting whatever it comes into contact with. So it's up to the owner/driver to understand how his/hers driving habits contribute to it's survival or it's death and make the necessary adjustments or continue to fail one of the best "Little" transmissions ever made(200-4R).
Kevin.