Thank you so much to everyone for helping me to think this through. I still find the situation very perplexing, but at least I feel that I have some options to consider at this point.
a) My DH thinks that he can help DD to "edit" her responses to be in line with what Mr. Fantastic is seeking-- his suggestion, therefore, is to have DD run EVERY bit of additional writing for the class through him. Pro: may work, since DH has a much more 'flat/technical' style than DD does innately, and he works in an engineering environment with similar communication barriers. :ahem: Also doesn't force DD to alter her voice as a writer, or her principles as a person. Con: sends the message to my DD that she isn't 'capable' of earning her own grade in the class, and she objects based on ethics, feeling that this MIGHT violate the honor code.
b) Let her take the B that she's likely to earn without any additional intervention. Pro: no more angst necessary, no more potential ruffling of teacher feathers. Con: it's wrong. Oh, and potentially damages DD's class rank, which is one thing if it's deserved (say, if she were 'choosing' not to work very hard at physics or something and earned a B rather than an A), but quite another when it's a personality conflict at work. I hadn't mentally framed this as an integrity issue for DD, though-- and that has been a helpful perspective for me. Recall that DD's sole goal for now, academically, involves class rank. It's about the only 'realistic' and tangible goal that she has in this particular setting. She wants number one, and a B in this class jeopardizes that larger goal.
c) drop the "honors" course in favor of another teacher, or investigate the possibility of converting to the AP course (it's almost nine weeks in, though... ay yi yi... she'd have to double time it to make up the time that she's missed) Pro: AP comes with greater depth/difficulty, and also with a better GPA weighting. Con: OMG, the sheer VOLUME to make up, though... As for dropping to the non-honors course, that comes with a GPA weight penalty. Obvious 'con' there.
d) take a break, attempt further remediation involving people higher up the food chain. I've not ruled this out, but I fear burning bridges at this point. I'm probably GOING to call the counselor next week either way-- even if only to figure out what the other options are under c). Pro: better data, possibly better communication with teacher, Con: irritating the teacher further at both of us may make him even MORE intractible. It might even get him "in trouble" and that's really not my goal here, since as noted, he seems to be an EXCELLENT teacher for at least some students, and probably for the students who are more typical in this model.
e) Have DD take a break and hope for a better future after she's calmed down some (and maybe, quite honestly, after the TEACHER has calmed down some). Pro: hey, less emotional thinking is always better for communication. Con: the fundamental problems remain unchanged in the situation on all sides.
f) Have DD attempt to earn perfect scores in the class, keep her head down, and try to write the way he wants. Our advice to her thus far has been:
Don't use ANYTHING that you've learned elsewhere in ANY of your writing unless you're specifically directed to it. Stick with the textbook definitions and explanations. Verbatim where possible.
Write simply-- and aim at a kinda slow middle-schooler.
Write 'persuasively' as if you were debating.
Pro: lowest activation energy, and seems least confrontational to teacher (who is a real nut about authority/respect issues), also teaches DD how to deal efectively with someone like this-- if it works, that is. Con: means allowing DD to give perfectionism full reign, at least in this class. May serve as an unwelcome distraction to her when she needs to focus on AP Lit and Physics since those are academically appropriate. Compromises her principles, since she tends to regard this kind of over-simplified, cherry-picked writing as inherently biased and disingenuous if you're doing it ON PURPOSE and pretending that it represents "truth." (Debate or formal legal defense is different because everyone KNOWS that it is what is taking place.) That said, I think that maybe she CAN write the way he wants. Probably, anyway-- it will just feel horribly "icky" to her.
Much to consider.