Is anyone else having problems just installing their watch app from XCode?

This occurs on my phone and watch, but not with a friend's using the same MacBook. XCode shows me my watch in the Watch App scheme device list under "ineligible devices" as:

TealShift's iPhone + TealShift's Apple Watch (paired device OS version)

Just the parenthetical part looks to me like a huge bug, like XCode has no idea what's wrong.

If I manually select it from Product > destination, attempting to run the app results in an error "The operation is unsupported."

Re-pairing the watch as well as rebooting the phone, watch, and MacBook made no difference. I did notice that the "copying symbols" process was not occurring for my watch, so that's probably related. This is really bad for my productivity, and I haven't found anyone else with this problem online.

I've got XCode 7.0 iPhone: iOS 9 Watch: WatchOS 2