I used to be pretty decent at keeping my bikes maintained, but I guess I've gotten a bit rusty.
The rear mech was driving me nuts, as I couldn't quite get it adjusted right. No wrecks or anything that should have been able to knock the mount outta whack... or I didn't want to think about having to go that deep.
Turns out, when I installed the new cables, I ran the rear derailleur cable along the wrong side of the pinch bolt... which threw off the pull just enough that I'd never get it to shift right across the range.
All good now. Just got home from an 18 mile group ride, and Jake shifted beautifully.
I'm feelin' pretty good after the ride, too. Great thing is... after all the procrastination and avoiding the issue, I'm starting to feel like I can be a real cyclist again.