Interesting question. Short answer is no. I read your question and realized I didn't know the answer to it. So I opened up the game to check, and was surprised to find out that the only attribute potions you can craft are the minor ones.
If you right click any attribute potion, you'll see that there isn't an option for combining. Even though they do show up in the crafting interface, they can't be combined with anything. (They really should take a look into this; only items that can be combined with something can show up in the crafting interface)
That said, at the end of the game, I had a bunch of these, a few of each type. I don't think they're *that* rare, but I didn't find them *that* useful either. In most cases, I could always spend that one AP to do something else that had more "dramatic" result. Even the medium ones give you only +3, which is not that great. You can just spend that one AP to cast Peace of Mind instead, which gets better and better as you level up. And the scrolls are quite abundant. I always had a stack of them on each character.
So yeah, these potions are rather irrelevant, if you ask me.
Last edited by Try2Handing; 17/12/17 10:18 AM.
