. . . But hopefully not in this case.
It would appear that I've managed to replace my dead iPod battery (it wouldn't hold a charge, but worked fine when plugged in, and I mostly used it in the car) without a major incident.
I managed to get the case apart on my second try, without denting, bending or scratching the back. I replaced the battery, reattached the HD snap/surface connector (I can never remember what those are actually called) and started to charge it.
After a bit I turned off the lock (thus confirming I hadn't screwed up that mechanical linkage) and it turned on, spun up the HD and all of my data was there. It even synched tracks that had been played. So far everything looks good, but I haven't tried to use it on battery power, since you're supposed to charge it for at least 3 hours before using it, and that ends in . . . Oh, 10 minutes ago. Well, I'm tempted to charge it completely before trying to use it.
Oh, and for those who are interested (3G owners, your batteries will be dying eventually) WeLoveMacs.com has replacement batteries for $25. Yes, they're in Santa Clara, but trust me it's worth your time to spend the few bucks on shipping to avoid dealing with their "retail" store. *shudder*
UPDATE: After it was fully charged, I tried playing a few songs on the new battery. As HAL once said, "I'm completely operational, and all my circuits are functioning perfectly." Yay! iPod back!