I cannot see this card doing anything worthwhile in a Scrying Pool deck. First off, I would be buying Pools with every Potion buy, and besides, what benefit is it to fill your deck with terminals (as replacement for coppers) when they are basically useless en masse? Yes, obviously it is important to clear out the starting cards to make a Pool deck work, but I would require a better trasher to begin with before I went this route.
Only Chapel, sometimes Remake (where there's a 3 cost action), and sometimes Remodel (when there's a 2 cost action) move you to a 100% action deck more quickly than Transmute does. For the purpose of a
Scrying Pool deck, it's a faster trasher than Steward, Lookout, Loan, Bishop, Salvager or Moneylender. And really, if it helps you draw your entire deck, it doesn't matter that it's terminal. I've had ~10 terminal actions in a Scrying Pool deck, and I didn't care, because I drew my entire deck every turn regardless. Plus, it doesn't destroy your economy, because it turns your Estates into Golds. If you have 3 Scrying Pools and 3 Gold, and the rest of your deck is actions, then you draw them every turn (almost) guaranteed.
Oh, and if you have the actions it can net you 12 or so VP in your last turn, which is not nothing, even in a Colony game. In a Vineyard game, the value of changing your 7 starting copper into actions, thus making all your Vineyards +2 VP speaks for itself.
