I definitely see bits of what you're talking about in our situation, OA. ENFJ does have a tendency to settle on what she thinks is the best option, and then argue when other solutions some up. Not all the time, though--she's aware of how she can be sometimes (she is very self-aware sometimes, and not aware at all other times).
Here's what we came up with last night. We had a really good, open discussion last night (ENFP, INTJ and me). First and foremost, they feel like I do--they do NOT want to break up the band over something so stupid (not the ENFP problem...read on). Larger than the problem I had originally posted about is the fact that this week, the drummer has been butting heads with ENFJ because he feels underappreciated. He is a good guy, but a bit of a redneck, and anything even approaching conflict with the ENFJ and him turns into a giant mushroom cloud of disaster. Basically, the cycle is, she doesn't really respect him, he puts up with it, but then he gets resentful after a while, he calls her out in a way that is guaranteed to make her see red, she wants vengeance. ANYWAY, ENFP didn't even know any of this was going on, and he immediately took the tactic of fixing this thing, no matter what. So we were really all on the same page, and I tried to ask them questions about how they ideally wanted to work, and what things they thought it would take to fix all these communication/working issues that keep cropping up.
As far as the OP stuff, I could see firsthand that both ENFP and INTJ were genuinely frustrated at being given a list of things to correct AFTER the gig, when they feel like if we'd had practice, we wouldn't have "sucked" in the first place, which is what they read from those emails. Definitely a fair point. They really do hear those "morning after" emails as code for "you suck. fix it so you won't embarrass me again." As INTJ put it, "We're not trying to suck just to piss her off. Nobody wants to suck." (And they don't suck; they're great players. We just had a few teeny glitches that needed tightening up.) I agreed with him and also reassured him that in ENFJ's mind, she's being kind by not calling people out, and also, she kind of feels like it goes without saying that they're great players...and that those things she points out are, for her, the only things that need fixing out of a whole evening of solid playing. She's thinking about little things that can make us sound better as a whole. So, ideally, both sides need to be understood, and I'd really like to work out that whole process between them and ENFJ.
They also (including drummer) feel like she has no right to complain about things if she's going to bow out of rehearsal. Turns out, ENFP had been TRYING to fix all those things, but he'd been matching it and comparing it to the original studio recording, feeling like he'd got it, and then get called out for it again. He said, "She's obviously hearing something differently than I am, and unless she's there to tell me when it's "right," I won't know, and I'll keep getting it wrong, because it sounds right to me." Which has to be infuriating. I knew what ENFJ was talking about, though, so I asked him to play it for me, and I'd do my best to help him figure out what she's wanting. Turns out, he was playing it absolutely perfectly when it wasn't plugged in. Perfect dynamics. Beautiful. But when he plugged in, he had a compressor effect that helped with sustain, but evened out the dynamics. BINGO. Then we figured out it sounded better when he played it fingerstyle instead of a pick. Totally solved the problem (we hope). We worked on the other songs, too. Hopefully that will be a show of good faith to ENFJ, and she'll be willing to meet them halfway. That will be a start toward opening the line of communication.
Funnily enough, ENFP and INTJ are kind of willing to let ENFJ be ENFJ, and put up with her quirks most of the time. They said this voluntarily and outright. They know she's not likely to change, and talent-wise, she's worth it. They're willing to flex and flex often. I pointed out to them that that always works until it doesn't. We will still periodically have these blowouts unless we figure out a way to accommodate each other, and that includes ENFJ. The immediate problem is getting ENFJ to the point where she'd be willing to have a band meeting about this stuff. But they really are mostly concerned with keeping the band together.
As far as the drummer situation, he doesn't know he's in the crosshairs. ENFP suggested we go to him and let him know what's going on, and that we get him to agree NOT to engage ENFJ directly over email at all. It ALWAYS explodes in his face. Drummer will have to be the bigger person, at least in the beginning, and that might be enough to soften ENFJ towards him. He may also have to come to terms with the fact that he's not ENFJ's favorite person, but the rest of us like and respect him. It's NOT ideal, but it might be reality. And they might eventually understand each other better with the pressure taken off.
The immediate plan is kind of a Band-aid (ha!) situation to save the unit. But with the success (hopefully) from that, we'll have a standpoint to broach the subject of a band meeting to clear the air and come up with a healthier way of interacting--one that makes everyone feel like an equally valued member.