Hey @Hunter thanks for this topic, it's very near and dear to my heart too. So much so that I'm in the process of preparing a blog post detailing a bunch of techniques (10 so far) that I've used to conquer the inner editor.
For me, the first step in conquering the inner critic was learning Dramatica -- studying it, applying it to my own stories, and working with Jim at Narrative First. Once I started to "get" Dramatica and could see how my ideas fit into complete argument stories (sometimes with a little tweaking), it gave me tremendous confidence that I could build the bones of a good story. At least at that level my inner critic is either quiet or helpful, fulfilling his role of calling out problems and inconsistencies without overstepping his bounds.
BUT when it came time to actually write a novel first draft, unfortunately, that confidence did not transfer. I'd feel in my heart my story was really good at the outline level, but that almost gave my inner editor more ammunition: "this scene sucks! it's not good enough for this story!"
Enter the respected writer and writing teacher Holly Lisle. Most of the inner-editor-conquering techniques I use have come from her classes, forums, or podcast. Since I began her How To Think Sideways class 1.5 years ago I've written around 350,000 words of first draft material on a novel and several short stories.
I'll put more detail in my blog post, but if anyone is interested in taking her How To Write a Novel class with me, I'm planning on starting it within the next month. But the class is only available for the next day or so -- it's currently still in development so she's limiting enrolment (and the current price is significantly discounted because of that too). The "in development" phase is actually a significant bonus rather than a detriment, since the first wave of students gets to influence the content and development of the class, with lots of feedback from Holly herself.
Anyway, just an idea. I don't mean this to be a pitch or anything, I've just found that Holly's methods for working with your "muse" really complement an understanding of Dramatica. (Also, she doesn't go into story structure much which is great because it means she doesn't get anything wrong. She just makes vague but wise statements like "every story needs its own structure".) And I'd love to see some Dramatica peeps over there.