Timesert and TTY Victor Reinz headbolt question

[ahlem]

2001 3.0
I timeserted the block and thought it was a successful effort.
I torqued down the "lightly oiled" headbolts to 30 foot pounds per the Bentley manual. So far so good. Then the first 90 went 13/14 OK with one bolt on the passenger side between 5 and 6 "yielded" easily before the first 90.
Now what? I figured I'd have to do something to remedy this so I did the second 90.
Creaking and popping on about half the bolts and I stopped short of 90 on those. The other half hit 90 degrees and a couple yielded short of 90.
When I say "yielded", I mean that they seem to have stopped requiring the same torque as before.
Do I need to tear this back apart to see what happened? Is this typical of Victor Reinz headbolts? Did I screw up the Timesert process?
The exhaust manifolds were a PITA by the way and I don't relish the thought of having to redo this but even worse would be to put it the rest of the way back together and have a headgasket failure..