As you know I'm not working from AW experience. I'm working from having read the AW rulebook pretty closely, and using the methods (perhaps a little roughly and readily) in Classic Traveller play.
But it seems to me that, in a fundamental sense,
all the GM/MC does in AW is to make moves, either soft ones or hard ones. Upthread I've already quoted the text from p 117 (1st ed; I don't have 2nd ed), and there's also this on p 116:
Whenever someone turns and looks to you to say something, always say what the principles demand. . . . Whenever there’s a pause in the conversation and everyone looks to you to say something, choose one of these things [from the list of MC moves] and say it.
I guess the exception to what I've just said is the GM/MC asking provocative questions, though often these will also be moves - particularly offering opportunities or setting up some incipient badness. Of course there's also the GM having fun and kibitzing like at any table, but that's not them acting in their "official" role.
I don't see "saying yes" as part of the AW lexicon.
If you do it, you do it - there is no "get out of rolling via GM fiat". That's why different PbtA games need different basic moves, to reflect different premises about what sorts of actions are high stakes.
In AW 1st ed, here's how the example of play, under the heading Moves Snowball, begins (p 152):
Marie the brainer goes looking for Isle, to visit grief upon her, and finds her eating canned peaches on the roof of the car shed
with her brother Mill and her lover Plover (all NPCs).
Marie's player can tell us what Marie does -
going looking for Isle - but (given that she's not acting under fire, nor doing it by opening her brain to the psychic maelstrom) that doesn't trigger a player-side move. So Baker makes a move in reply - he's the one who tells Marie's player that Marie finds Isle, Mill and Plover sitting on the roof of the shed eating peaches. Baker doesn't tell us what move he has made here, but it seems like he's
offering an opportunity. It's less clear what principle is governing this - we need more context - but given the remark to Marie wanting to visit grief upon Isle, maybe Baker is
looking (at Isle) through crosshairs. In other words, he's deliberately made a move that steps up the conflict and stakes at the table.
Everything else being equal, Baker could have made a different move - say
Isle's nowhere to be found in the hardhold - which would
announce offscreen badness, and might be looking at Isle through a different set of crosshairs. The MC is not obliged to let Marie meet up with Isle just because that's what Marie's player wants; and there is no analogue to a Circles mechanic by which Marie's player can oblige the MC to frame an encounter between Marie and Isle.
I think that
@andreszarta is saying the same thing about the locked door, or the T-intersection.
I mean, suppose that Baker tells Marie's player that Isle is nowhere to be found, and Marie's player asks "Is there anywhere she might be that I can't check?", the MC can answer (surely!) "Well, the car shed's door is locked, so you couldn't check in there." That's
offering an opportunity, most likely with a cost; and is
responding with <naughtiness>. If Marie's player replies, "I wait until no one's nearby, then bust it open," well that sounds like Doing Something Under Fire. And so we resolve that. Or if Marie's player instead replies, "Bugger! I go to find Keeler the Gunlugger to help me break into the shed", well that's good too - the MC might ask Keeler's player what Keeler is up to, and go from there. Or maybe Marie opens her brain to the psychic maelstrom, hoping to learn if Isle's locked in the shed. Etc.
To put it another way, perhaps more formally: in AW there is no process of
framing, player-side move, resolution, re-framing as there is in (say) Burning Wheel or Prince Valiant or a 4e D&D skill challenge. Player say what their characters do, perhaps after poking and prodding via questions from the GM/MC, and either that triggers a player-side move (if you do it, you do it) or else the GM/MC responds with one of their moves, and we keep going until we agree it's time to stop.