Although I see why it would be nice to have PISORF available through preps, I don't really see where there would be a problem with potential game-breaking exploits with it if this were to stay the way it is until release;
If there is an exploit and we don't want to scum for it, why should new players scum for it more than we do?
And if an exploit is found, where is the incentive to scum for it when you can beat the game in various other ways that don't require much scumming?
So either pisorf and therefore the exploits get available through preps and the exploits can be effectively found or it stays the way it is and there is no incentive to scum for exploits. Sounds solid to me either way, I don't see how one thing depends on the other.
Although in general I'd also be in favor of a pisorf prep or a class that starts it. I don't know, call it smite and give it to the crusader instead of the extra altar and make it count as a normal attack regarding momentum or something.