I don't know about you guys, but revising a long novel is a--ahem, not fun. Especially not when you've been tearing your hair out over the first five chapters forever. I can't count the number of revisions on this particular beast, and finally I stalled out altogether. But, being at a particularly low point here a couple of months ago vis-a-vis making a living at fiction, I gritted my teeth, hauled it out, and had a brainstorm that sort of broke the logjam. So I redid the opening, retitled the thing, rewrote my cover letter, and sent it out. Presto! Somebody asked for the manuscript. So, oh my, did that ever give me motivation to overhaul the rest double quick. For the first time, I actually feel like this novel might be done, readable, marketable, maybe even attractive to a publisher (oh, please God). I really love the trilogy (I write fantasy, so is there anything that doesn't evolve into a series?), and I really, really want to see these books in print. Somewhere besides Lulu, that is!
Keep your fingers crossed. The lesson here, I guess, is that sometimes it pays to go bass-ackwards at a problem. In my case, I tossed the query out before the thing was 100% ready to go, knowing that likely I would either not get a bite at all, or one so delayed I had to work on it. The bite came faster than expected, but it was all good, because geez, did it ever give me focus. I work especially well under the gun, for some reason. I created my own de-blocker and motivator, and I feel really good whether or not this particular agent will sign me on, which I hope, because it's a great agency. The book looks good (to me) in its current form, and I am celebrating a bit today because now I can move on to revising other stuff in the drawer and quit feeling bad that this one is still moldering in there.
When in doubt, go for it. Really, what have you got to lose?