well.............
The starter passed the tests.
I ended up having to replace the battery.
When I put it all back together, it actually did fire and run for about a minute. Once it struggled up to idle, it sounded fine. Even blipped the throttle a couple times w/out any hesitation or wierdness.
I got out to tighten down a couple bolts and it died. Tried starting it back up and it wouldn't start.

I'm wondering if (a) it's flooded (kinda smells like it may be) or (b) I'm chasing a faulty sensor.