This may be intentional but it seems strange that when you drink a potion of remove curse you lose exp. I can understand for clerics casting it but I assume the fact you lose exp for the potion is a bug.
I believe it's entirely intentional. Wands of remove curse strip the exp, as do misc items with remove curse uses. It's a cost now attached to the use of the spell, because the spell now has a huge boost related to the withering.
True, but you'd think the whole point of finding devices is that they mean you don't have to pay the XP cost, it was paid at creation.
I believe the idea is that as a portion of the Withering is stripped away by the spell, it takes some of YOU with it, regardless of what the creator intended. Side effect of having the withering when you apply remove curse. I would bet a PC who was not afflicted by the Withering would lose no XP.
Sounds logical, except that the XP lost is always from the "caster", whether they cast a spell or use the item. So if you ask a Cleric to cast Remove Curse on you, they lose the XP, but if they scribe you a Remove Curse scroll and you use it, you lose the XP.
EDIT: Also, I know I've never seen them advertised or bothered making them, but it should be possible to brew Boon Potions. They'd be rather handy in the new setting. If they cost both the user and the creator 150 XP a pop, that's going to suck though.
I thought it was more to stop clerics spamming remove curse on people for free. That's sort of the advantage I thought to using an item, no exp loss because you aren't putting any magic in to curing yourself as you would if you cast the spell.
Make creating the wands cost a lot of XP and reduce the amount "Remove Curse" items from the loot table, but remove the XP penalty by casting it (from an item) imo.
Sounds like a ridiculously easy way to relevel for those inclined to do so.