Ah, I see. I seem to recall reading about that now. What that does is force all apps to use froyo apps2sd even if the developer hasn't coded it in. It's basically the same idea as forcing apps to the sdcard with titanium backup. I would highly recommend you not do this because:
1) It's an all (almost) or nothing option. It will attempt to move all apps to the sdcard.
2) If it moves an app that uses widgets, I would assume it works like any other app moved via apps2sd, and won't allow you to use the widget anymore.
3) If you connect your phone to your computer and mount as a disk drive, way more apps will be unavailable during that time.
4) I've heard too many horror stories about forcing apps to the sdcard when they weren't necessarily designed to do so. This is (sort of) the same as what titanium backup does when you force apps to the card. Force too many, and you might be asking for trouble.
Personally, I would recommend you look into a2sd. It's a much better option if you want to move all apps to the card.