sway bars, tyres, ride height, wheel alignment, all seem to play a roll in it
if you power out of a corner hard i find the arse does come out, but not like a rwd, if you keep on the gas pedal, and point it where you want to go (dont overcorrect) it corrects itself... thats the idea of the ATESSA, if you dial it up to 50/50 full time i think it may do bad things