The hemming and hawing should not happen, you're right.

The problem here isn't on the player side. The GM is cheating. Accidentally, but still cheating.

GM Cheating in Dungeon World

The GM cheats in Dungeon World when they speak without following their Agenda, Principles, and Moves.

There is no GM move called "make an arbitrary decision." There's also no GM move called "have a freeform social interaction." If the GM is following the rules, this kind of stall should not happen.

This is why the GM has rules, to prevent situations like this one, among other situations that qualify as failure modes to avoid.

Responding to a polite request, as the GM

The player's job is done: they've had their PC ask politely. There is no error on the player side of the equation and nothing to fix, no other moves to try to bend to fit the goal.

Since the “everyone looks to you to find out what happens” trigger matches, it's now the GM’s turn to make an appropriate move, instead of falling into “time for unstructured social exchange improvisation!” habits that they have brought with them from some other game.

(Recall too that moves aren't optional when triggered: when that trigger happens, a move must be made; this is equally true for GM moves as for player moves. The GM's turns has been triggered and making a GM move is now demanded by the rules.)

There are several moves that the GM could make. All of them, if executed with the Agenda and Principles in mind, should immediately add something new and interesting for the players to engage with, not just chit-chat.

The trick is to pick one, and then do a quick mental Mad Libs to fill in the blanks that the move demands. Let's assume the PC has politely asked for that magic sword:

• Reveal an unwelcome truth:

  “Sure, you can have my sword! It's cursed. If you can take it from me, I'd be more than happy.”

• Show signs of an approaching threat:

  “What kind of a person asks for a warrior's sword?” the bandit chief growls. She's obviously really insulted just by the question. It looks like she's thinking of giving it to you, point first, if you can't mend the situation. What do you do?

  or

  “This old thing? Uh, sure! Here!” he says breathlessly. He almost pushes it into your hands, and then runs off. It's a very fine sword, clearly magical and worth a lot. As you look up from admiring it, you notice a posse of civilians with torches and pitchforks lead by three members of the city watch running in your direction. They're shouting something that sounds awfully like “Thief!” What do you do?

• Turn their move back on them

  Possibly the simplest and most straightforward move to make: ask them to tell you why in the world their polite request makes any sense! If they're asking in the first place, they might see a good reason that you're not seeing.

  — Hm, you're just asking? Okay, well why do you think they would just give it to you?
  — Because the village owes us their lives and souls, and we're heroes. He'll probably gift it to us.
  — Huh! Well at any other time I'd laugh and so would he, but yeah, considering what you just did? Yeah, they gift you the sword. They even make a big ceremony of it. You're big damn heroes!

• Give an opportunity that fits a class’ abilities

  Have you got a thief in the party? Well...

  He laughs that off. “Just give you my sword?! You must be soft in the head.” He turns and walks off, shaking his head and laughing. But you get a good look at his sword belt from behind and notice it's worn... given the right chance, you could probably cut it quick. Want to tail him?

• Tell them the requirements or consequences and ask

  This is a staple of responses to polite requests. This prompts the GM to set a price, and ask.

  She says sure, she'll give you the sword. But only if you defeat her in single combat. She seems pretty confident too. What do you do?

  or

  “Sure. What's it worth to you? How about... that emerald necklace and arranging an audience with the Unmasked Lord for me? No? Well... let me know if you reconsider.”

  or

  “Hm, alright. Do you have three hundred crowns?”

  or

  “I tire of the burden. It is yours if you want it. But beware: the sword has a way of making heroes out of its bearers, whether they mean to be or not. Take it only if you are willing to shoulder that burden.” He holds the sword out, hilt first. What do you do?

The point is that the PC “just” asking is just the beginning, and there is nothing that says “just asking” is suddenly set in stone as the price at stake. The GM's job is to play to find out what happens, and to do that you pick a GM move, fill out its details, and play out that response. The result will almost certainly establish that there is a price beyond politely asking, either of in-game goods to exchange or in narrative branches the players must tackle. Rather than deciding, you add something interesting to the situation and then see what the players do.

So clean up the GM's side of these meandering social improv interludes, and you won't see stalls anymore! The GM might even be surprised by the things they spontaneously add to the game, faced with such circumstances. This is where Dungeon World shines: turning mundane, boring bits of play into pivotal moments, because the rules demand never doing something boring and stale.

A (Practical) Cast of Thousands

On the subject of group size, I would highly recommend not going above four regulars your first time out. Dungeon World is a game that demands a lot of the GM in play - you have to constantly keep in mind everyone's capabilities when you're pitching the setup to them and when they're pitching their actions to you. I've been running it for years now, off and on, and I can maybe take 5 people, or 6 on a very good day. You'll get a feeling for what you're capable of as you go, and a regular group can often entertain each other in ways that successive slots at a convention, say, just can't.

However, if you're anticipating a peripheral group who have some sort of interest in sitting down to play on occasion, I'd consider establishing a Crew, from the sadly-never-released Pirate World. The game was kickstarted and PDFs distributed to backers, but I can't find anywhere to buy it. (If anyone knows otherwise that'll be a nice surprise.) In a game of Pirate World, Crew are more than hirelings but less than PCs, who accompany the PCs regularly on their adventurers. In a game more based around a hub town or towns (and a notable Dungeon or Dungeons), Crew can be adapted to be the colorful townsfolk and friendly monsters and animal companions and such that you may be familiar with. They're statted out about like this:

Innismore, Irascible Alchemist

Hunger: Highly Illegal Ingredients

Benefits: Know something vital about a powerful adversary

Mix up a potion to overcome some obstacle

Loyalty: 2 Resilience: 1

The Benefits are the things they can do for you. When you want one of your Crew's Benefits, spend 1-Loyalty to get it, but first roll +Loyalty. On a 10+, that's the end of it. On a 7-9, the GM chooses 1; on a 6-, they choose 2.

• You must satisfy their Hunger before they'll help you again
• You must Defy Danger or otherwise put yourself at risk in order to make use of the Benefit
• It costs 2-Loyalty instead of 1.

Benefits are very conceptually similar to monster moves; that is to say, they don't have to be anything more than descriptions of the cool thing that you want the creature to do. When the PCs take advantage of them you'll usually have some kind of context to flesh them out (in this case, the obstacle or adversary PCs need to consult Innismore about). You can also define Benefits more strictly, as something to guarantee the PCs they wouldn't otherwise be able to find:

Whitecrush, Lizardfolk Shaman

Hunger: Forgotten knowledge of magic

Benefits: Provide access to a lizardfolk safehouse (a safe place to Make Camp for one night, and folk medicine to cure one debility)

Dispatch a young bravo as a guardian (treat as a hireling with Cost: glory in victory; split 7 points between Warrior, Protector, and Loyalty)

Loyalty: 1 Resilience: 2

The Hunger is the troublesome thing they need PCs to provide them with. When you satisfy your Crew's Hunger out of more than a sense of obligation, they gain 1-Loyalty. Hunger is something to keep in mind when you're offering PCs opportunities - sure you could destroy all the cultists' horrible reagents, but maybe you can smuggle them in to Innismore. Sure, Wizzrobe could copy their ritual notes into his own spellbook, but they'd also be worth bringing to Whitecrush. That sort of thing.

Loyalty is most easily altered through asking for Benefits and feeding Hunger, but it's there to represent how this person feels about the PCs. Doing things they would appreciate or putting them in danger can also bump it up or down, but it's proper sportsmanship to tell the PCs the requirements or consequences if they're making a decision and loyalty is on the line.

Resilience is a rough measure of how much damage they can take, equal to about 1 for every 5 full hit points they'd have as a monster. Each significant attack takes off 1 resilience, and if they get whacked at 0 resilience left their fate is completely in your hands.

Improving Crew is certainly possible over time, as PCs establish more of a relationship with them. If it seems like they'd gain something new, feel free to write some of your own moves that key off Loyalty to reflect these new capabilities - Whitecrush's bravos might get more points to distribute or she might develop some rituals of her own, or Innismore can kit the PCs out to "field test" some alchemist grenades (roll Loyalty and you get hold on low rolls that you can spend to activate complications).

When someone on the periphery wants to jump in for a session, they can pick up one of the Crew. They can use the main benefits as normal - they make the choices about costs instead of the GM - and they can also roll +Loyalty to help the main PCs in other ways, anything an Aid roll might work for. On a 10+ the PC they're helping gets a +2, on a 7-9 a +1, and on a 6- in addition to what the GM says, they feel obligated for letting everyone down and gain 1-Loyalty. In general they won't be exposing themselves directly to danger, but you've got Resilience for those cases where they get caught out.