Auto trannies definitely hold back much of the power. A friend of mine just put in a Comptech SC in his 3.0 CL. 0-60 times decreased only by .6 seconds.

I know some people that have SC's on their BMW's A/T's.
It's well aware that Honda auto trannies are weak. To slow down the wear down due to F/I, my friend installed a tranny fluid cooler. Much of the damage is caused when the A/T fluid boils.