Kev i dont agree with you on that one.

When i do a head gasket i always follow the same protacol.

1. remove head send it away for pressure check and skim.

2. remove dowels, clean head and check for true.Run all the bolts into the block with a little lubricant checking they run free all the way. Lube bolts and washers before refit.

3. clean both faces before refitting head using torque sequence and settings as manufacturers spec says.

But how do you believe strech bolts work??

I believe they stretch when under enough pressure to stretch. This would be when they are tight enough to stretch if as you say i have over stretched them(if they are stretch bolts that is?) Some of them were already overstretched before i added the final torque as they didnt move at all or they werent over stretched and i torqued the others that did move to the position where they are now stretching.
Right or Wrong??

Either way i believe you need all the bolts at the same torque as they are now.