The other issue, was that based on what was going on with the main character, several of them doubted the motives of one of the supporting characters, which seemed to lead them down all sorts of rabbit holes I hadn't intended (although, I had, in fact, purposely written her to be...complex, so it's not surprising). Without giving anything away, I'd meant for her to be a good person with a complicated set of behaviors and morals that live in the gray area between acceptable and borderline-sociopathic. Cheerfully immoral, in other words, but in a good way. She genuinely cares about the main character, and wants him to get better. Her way of helping is just questionable, is all. I like her (who am I kidding? I love her!) She's fun, which I think this very dark work may need to break up some of the horror. But I get my crit-mates' points.
And this is MY point. I loved the idea of not revealing the main character's name in the prologue. I love my (slightly) sociopathic supporting character. But as William Faulkner, who famously advised writers to "kill your darlings" ("murder your darlings, English writer Sir Arthur Quillian-Couch said even before that) would no doubt remind us all: our responsibility is to the story, not to any one character or plot point. If it doesn't serve a purpose, or goes against your purpose, then you have to get rid of it. Be ruthless. Ignore the hurt looks of betrayal your character gives as you chop her out of your story. The story itself will live on and be better for it. And you can always resurrect the character or subplot or scene in another book, or even in another part of the current work in progress (what I intend to do with the character I've been referring to).
So, I've been giving the matter some thought, trying to decide if I actually agree with my crit-mates. As for the prologue: No. Not really. It's actually been done. By Stephen King, in 'Salem's Lot. The prologue occurs after the story itself, and he only refers to two of the main character as "the man," and "the boy." You only figure out who they are later. (The one thing he did do, that I didn't was to show the reader that the prologue is present day, and the story that follows, a past event, by having the characters reading a newspaper article about the events that have already happened. Mine gave the reader no such clue, resulting in much of the confusion.)
However, two things have made me decide to follow the advice of my CMs after all. The first being that King has already done it (I hadn't thought about that at all when I wrote the prologue), and done it better. King is probably not the only one to have done it. And truthfully, I don't think doing it would matter in the least. The fact is, I think you'd be hard-pressed, indeed, to find something Stephen King - or some other famous writer - hasn't done before you, and better. I would just prefer to find another way, now, having seen another writer has done it. The second, more important reason I'm going to do it, is that I've thought of a way of revealing his identity in a way that will actually add to the tension and creepy tone of the novel. And I'm going to make it present-day, which will move the story forward into the first chapter.
I agreed about the supporting character, if only because I haven't written her as well as I conceived of her, and I can see how she is a distraction, which I definitely do not want. And now that I've changed the timing of the prologue, it not only makes her moot for the scenes that she's in, it would actually make the main character's judgment and motives extremely suspect. He just wouldn't link with her the way he is now after what happens in the prologue. So...she goes (for now).
So let this be a lesson to you. To make your story the best story it can be, to pull the reader in and keep them riveted and invested in your characters, sometimes the best thing you can do is take stuff out. It'll hurt. Sure it will. But what's left will heal up nicely.