Does any of the GM literture state that these bolts are in fact torque to yield? I have my doubts. TTY typically reqiures replacement each time you install. The proceedure for the head bolts with the additional degrees is typical of a TTY install, but the proceedure is the same for main caps and rod caps, and I never replace them.
I have sucessfully run a motor with re-used head bolts and re-used head gasket, both had been installed, fired, raced a few laps, and then disassembled. They were re-used as a test with no issue. This is on a stock HO build. Went 8 nights on that setup with no issue.
Additionally torque to yield bolts typically have a necked section where the yield occurs, replacement felpro bolts are threaded the entire length. If you actually torqued to yield on the bolt it would not hold the torque the next time you applied it.
I'm not recommending re-using either by any means, I ran at my own risk knowing I had to do a rebuild if I was wrong.