Just to put a cap on this self-indulgent thread...
Long story short: Big boss believes it might be a problem, but wants data to back it up. Apparently, my company manages numbers, not people. He says he'll talk to my boss about my concerns, but says he can't actually go after the problem unless he can show (again, with numbers) that she's overbooking resources and not managing schedule properly. Not only do I not have access to the numbers he wants, but even if I did, I would have to spend so much time collecting them that I'd be making my lack of time problem even worse. A perfect example of the "chain of discouragement" in action.
So, the good thing is I now know what I need to do. Job search is already throttled way up. If it takes too long, I might have to ask for a transfer to another department just to maintain my sanity, but that has the potential of making things worse, since it takes months to do even a lateral transfer, and there aren't a lot of open req's anywhere. Even if I did find a dancing partner somewhere in my company, I'd be expected to "transition knowledge" (aka work both jobs at the same time) which wouldn't exactly help my situation... Maybe best bet is to stay put, try to tread water, and get the hell out of Dodge as soon as I find a job worth jumping ship for.
Anyway, I kinda feel like the alcoholic who's had his moment of clarity now... I know the path I need to follow to make things better, now it's just a matter of doing it.
Thanks for all the input, guys, I feel kinda silly for wasting my time (and yours) trying to defribulate a dead horse, but a couple weeks ago, I really felt like the job was worth agonizing over. Now, it's just a job, and I'll find another.
I feel much, much better now.