Okay, so you try to play BoM while it's in the trash. The two things happen, then you play it as Feast for instance (could be anything). But when does the set-up effect happen? Doesn't it actually happen before you even get to playing it, so that it never becomes Feast? Remember, the effect was set up before play, and will trigger the instant the card is not in play. If that is the case, then you never get to play it as Feast. It will still be played, but as a straight BoM, which does nothing (same as playing BoM with no card cheaper than it in supply). I think this is the correct way of looking at it.
My point is that the card doesn't have to "be" Feast for it to be played "as" Feast. The "play... as" and "until it leaves play" clauses are two in-principle independent effects.
I see. Well, now we're getting into exactly what Band of Misfits does again. Partially you have to think about the intention of the card to understand how it works. That is partially what I did to figure out that it had to trigger before-play and then set up an effect to happen when it's no longer in play.
So does the first effect actually mean that it's played as a Feast without necessarily being a Feast? The second effect then would actually do two things: It makes the BoM a Feast
and it sets up the effect to turn it back to a BoM. Remember also that the first effect makes you play it
"as if it were" the chosen Action card. It's not just the card text that's followed: the whole card is copied, including name, types and cost. (If you were to play the Feast as an Attack card it would trigger an Urchin in play for instance.) So it seems pretty clear to me that the part in the second instruction that says that BoM "is that card" clarifies how the first instruction works, i.e. playing the BoM-as-Feast means it is a Feast. Although the second instruction does set up an effect, I don't think the two instructions are wholly independent of each other.
[EDIT: Donald has actually said the same thing, in this thread! http://forum.dominionstrategy.com/index.php?topic=4083.msg87477#msg87477]Having read the entire thread I don't see why there is such an issue here. I think it would be really sad if some kind of special ruling was deemed necessary, the situation does not seem so complex.
Perhaps you can make a compelling argument that you don't get to BoM-Feast twice, or that when you Procession-BoM you don't get to replace your trashed BoM with a $6 action. However, I really cannot see that it is intuitive to play that way. Firstly, and by my count most importantly, I do not think it is in the spirit of the cards played to deny the second Feast - it seems counterintuitive
Actually I think this might be the most complex card interaction I've seen so far in Dominion.
I do agree with you that it's in the spirit of the card that it lets you BoM-Feast twice with TR, and it's probably the intuitive interpretation for most people. However that you get a $6 Action with Procession-BoM is not so apparently intuitive for everybody, but in any case it's covered in the FAQ.
Anyway, it was important to me that it wasn't only intuitive, but that it was according to known rules about Dominion, not least of all because I maintain a FAQ on BGG where I try to include all known rulings.
So if you TR on BoM as mining village, you would gain 4 coin if you selected the "trash this card for 2 coin" option both times. Is that correct?
No, the point of the current ruling is that Throning a BoM-as-Feast or BoM-as-Mining Village, is the same as Throning a Feast or Mining Village.
[EDIT: Okay, this was answered.]