Cleveland pop-up dome pistons, as best as memory serves me, have 12cc to 14cc domes. In regards to a 4" bore, every 0.005" change in clearance is equivalent to 1cc. So to use a head gasket to correct the dome volume of a pop-up dome piston would require increasing the thickness of that gasket by 0.060 to 0.070. The net result would be a gasket that is kinda too thick.
Horsepower increase based upon compression is not linear, it is logarithmic. There is a law of diminishing returns. Increasing compression from 10:1 to 11:1 does not increase horsepower as much as increasing compression from 9:1 to 10:1. And increasing compression from 9:1 to 10:1 does not increase horsepower as much as increasing compression from 8:1 to 9:1.
In the end maximum compression is largely based upon fuel octane, and next upon combustion chamber dynamics. Since the combustion chambers of iron quench chamber heads and SVO aluminum heads are identical, I would not expect there to be much difference in power or maximum octane. I would hope calm minds see the logic in that.
I have heard the arguments for iron heads expressed by Pantera Doug expressed previously (decades ago) by experienced practitioners of the dark hot rod arts. Such anarchic ideas were expressed by folks smarter than I. There appears to be many advantages to iron. We in the world of small automobiles (sports cars) tend to appreciate elimination of weight above other priorities.
There are three types of compression. The static compression, the dynamic compression (which used to be called effective compression), and the operating compression (which if you think about it, is actually the dynamic compression). We can measure static and dynamic compression, operating compression is only learned by empirical data (experience).
Finally, I jumped on the net and looked quickly for info about compression. Here are the thoughts regarding compression by John Maher, proprietor of John Maher Racing. They seem to be right in line with what I have learned. So of course that's what I posted, seeing how I'm so starved for validation.
Compression - John Maher Racing