In fairness bleed, and the other concept are interrelated, as they both have to do with layers of seperation between you and the character-- some people play TTRPGs to stand in the 'shoes' of their character, which often has to do with winning and losing, fighting a dragon isn't something the characters just overcome in the story, WE AS PLAYERS are also trying to slay the dragon, or in the abstract to overcome the challenges and 'beat' the game, its the concept of wargame, but as applied to fantasy adventure story that sits at the roots of the genre. I 'as' Emrys the Wizard are trying to slay that dragon, if I don't manage it thats a failure state for me in playing the game, not just for Emrys himself.
Meanwhile, in some other games, there's more of a separation-- like in Masks, while the players are fans of their characters and want to see them eventually succeed (and that's usually how the stories the game is emulating end anyway) they're way more interested in creating all the drama that goes into that along the way, its not such a massive breach of etiquette when a player has their character stop doing things because they're having a panic attack mid combat, or surrender. I can have my Soldier playbook character Ronin, do something that will unknowingly put him at odds with the rest of the party, knowing it'll make things more complicated later, because we're not just doing our best to win, we're doing our best to have dramatic stuff happen.
Then all of that ties into the ideas of challenging the player, vs. the character, and how our emotional states bleed into our characters-- for instance if you and I are primarily playing in the first person, an argument between our characters might reflect our actual plans for what to do in that situation (regardless of the separation between what we would do in real life, vs. here) and therefore we might be personally invested in the outcome of the argument, rather than in the narrative implications of it, leading it to be more of an actual argument than just roleplaying if we aren't careful. If I'm really trying to slay the dragon, then when your character gets in the way of that, they're getting in the way of me trying to slay the dragon, not just Emrys doing so. That's part and parcel of bleed I think, when you want something, and someone else is frustrating your efforts.
Notably, this is also kind of in contention, how one 'should' play roleplaying games, some people lean all one way (you aren't trying to win, no matter what game you're playing) other people lean all the other way, and others are mixed, and then even express that mix in different ways (I draw the line at deliberate underperformance in solving the game's obstacles, within reason, before anyone brings up the idea of policing slightly un-optimized characters as a logical conclusion to that.) Heck, the differences are even baked into the different personalities discussed in the DMG player personality section-- the actor wants to express their character, the thinker wants problems they can enjoy solving, and so forth. I think that while DND and such can kind of support either, its very much more about overcoming the obstacles together in the game world, in the first person, thats just how the mechanics are designed, they're levers you pull to make progress towards solving problems.
