When I say metagame, I'm simply referring to a set of rules in the game.
So you would count all the action resolution rules in D&D - combat, ability and skill checks, spells, etc - as metagame mechanics?
Just checking I'm understanding your usage, which is not the usage I'm familiar with.
As far as your scene, I don't feel the need for game mechanics. Guess I'd have to see it in play to be sure I understand though. Thanks for trying to explain.
But it is really just a preference. I'd simply rather just run the scenario as a back and forth between PCs with no rules or game system involved.
But where I'm confused is when you talk about persuade one another. In D&D, the players talk it out. There may be a knowledge check here and there, but that's it. No player can influence another player's decision based on rules of the game barring magic. It sounds like that is not true for the scene you describe.
Re mechanics: I think
@Aldarc has already tackled this a couple of times, and
@Umbran also. There are different variants of Cortex+ - it's a family of systems that are related like (say) 3E D&D, PF and StarFinder.
The version I play is a fantasy adaptation of Marvel Heroic RP. Everything that matters in the fiction - be that on a PC sheet, or in a scene - is rated by a die, from D4 to D12. Actions are opposed checks. Players build their pools out of the traits on their sheets; the opposed pool is either an opposing character (PC or NPC) or the Doom Pool, which is a separate pool of dice that grows and falls with the action and various decisions that participants (especially the GM) take and which serves as an all-purpose source of adversity, GM-side power ups, and pacing management tools.
Social/influence actions can be attempts to impose Emotional stress (eg Wolverine is good at this), Mental stress (eg a cursed Crystal Hypnosis ball would be good at this), or Complications (eg You Will Help Me Kill the X-Men!). Like everything else, these are rated with a die size. If a character has that sort of effect on them, then whenever it would hinder them (eg if they have that Complication, whenever they're
not helping to kill the X-Men) the effect die is included in the opposing pool.
PCs can use these rules to try and persuade or bully or confuse one another. It's an expected part of the game.
In the situation I described, I (as GM) had also established a Scene Distinction - ie something that matters in the fiction, as I mentioned above - that was (from memory) rated at D8 (which is the default for a Scene Distinction):
Uncertain of What to do Next. This was not a "material" or "physical" aspect of the scene - it was a "mental" or "emotional" aspect of the scene, that reflected the fact that it was (in my view) in fact uncertain among the players what they should do next, with each (as their character) having a different idea on that score. By framing the scene in that fashion, with that Distinction, I made the resolution of the doubt and debate a focus of the action. As I mentioned in my play report, it was the player of the Ranger who succeeded in eliminating the Distinction, which meant that - in the fiction - he was the one who was able to resolve upon a course of action and impress it upon his fellows.
Obviously I'm aware that there are other possibilities, like - as you say - "talking it out".
There are several reasons why I decided to substitute a resolution framework for talking it out. (1) It's quicker. (2) It's more fun, in the sense that instead of back-and-forth bickering or disagreement with no guarantee of a resolution, it's a process that leads directly to an outcome via the procedures of the game. (3) It makes the issue of
leadership something to be settled by application of the mechanics, where everyone is - subject to their PC build - on an even footing, rather than something determined by out-of-game social realities at the table. (4) As I posted upthread, it produced a scene that was reminiscent of Aragorn, Gimli and Legolas at Parth Galen, or even - at least a bit - of the Council of Elrond. Which is fitting for a MERP/LotR game.
In other systems, when debate at the table has dragged I've used different approaches: in Burning Wheel it's a Duel of Wits; in Traveller, it's opposed throws with bonuses to the side that has nobles and/or Leadership expertise; in Prince Valiant it's opposed Presence checks (perhaps influenced by significant differences of Fame or other modifiers to prestige); in 4e D&D I used opposed checks once but can't remember now how the modifiers were handled.
In the Cortex+ LotR game I had little hesitation in framing it as I did, because the system made it easy the 4 reaasons above applied.
EDITed to add:
I need a metagame for combat, I can't imagine running a game without it that wouldn't devolve into Cops and Robbers where one kid says "I shot you" and the other saying "No you didn't".
"Talking it out" is a lot like this. Because at the table, unlike in an actual debate, no one has any reason to yield because there is nothing actually at stake other than the passage of time in the session. This is related to my reasons (1) and (3) above.