Fasteners, like head bolts/studs and con rod bolts work by being stretched to a specification for a given assembly. That's how they keep the parts together in the very dynamic and highly stressed environment they live in. Some race engine shops use bolt stretch gauges for con rod bolts. Torqued to a spec approximates the required stretch for that bolt. In most cases the engineering has been done so you know the correct torque spec for your application.
Using a little lubricant under the head of head bolts is a good idea unless your application calls out for a dry assembly. We used Cosworth rods in some of our race engines. The rods were supplied with a pouch of lubricant. I think it was a moly lube of some kind but they would never disclose what it was. Their instructions were very explicit: MUST use the Cosworth lube under the head and NEVER get any of it on the threads, use light engine oil on threads. Lube helps achieve the correct clamping force for the spec torque applied. A dry assembly can have enough friction so that the torque wrench reading is to spec but the needed clamping force (stretch) isn't.
Steve, You said, "It seems like the coarse thread bolts complain a lot when torqued 105 pounds". Do you use lube under the heads? The threads shouldn't be dry either. Make sure the bolt head seats are not gouged or distorted. Before installing the cylinder heads confirm the head bolts easily screw into their respective hole and to sufficient depth.
Bolts vs studs is a long discussion.