Torque to yield, head bolts...

the heads need to slide, like the exhaust manifold of a slant. so you get MLS gaskets and TTY bolts that offer a more consistant clamping force. Of course, they are a one and done (sort of, you pre-stretch them to a small percentage once then retorque. Crazy stuff. I ask the same of rod bolts: You torque them once to set the plasti-guage then you torque them again for the final load, so is that reusing? Then you get some ARP's and they say to resize the big end with new fasteners. Dang machine shops are making a killing.