For those of you who want to fix WotL's slowdown without messing with files on your PSP or don't want FFT: KO's changes, I've created a .ppf file with just the slowdown fix. Just patch your WotL ISO with the .ppf using PPF-o-Matic, and the slowdown will be fixed. You can find that .ppf file here. (http://ffhacktics.com/smf/index.php?topic=9208) Enjoy!
@Eternal It may sound as a dumb question but:
It is better to use the patch on a clean ISO or when you have finished every change of a hackmod?