Very cool thread, thank you for your time! I haven't looked at anything yet, other than to read through the posts.
On the topic of retarded cam timing with shaved heads, all I can say is that on my motor(when shaved .040" and with a .040" MLS gasket), my car ran like I expected it to with the cam timing straight up(any cam I tried, K, H, RSI Stage 1 NA and ENEM K13). I typically run cams 2-6? advanced to bring the powerband down for better around town use. If I have the cam gear set at 6? advanced, it totally kills the power above 5500-6000rpm. This suggests in my real world experience that the cam timing isn't as far off as one would think based off of what people say(.010"/1?). Or if it is, I like running camshafts retarded(but before the head work, I ran cams advanced a couple degrees with similar success as well, so..........).
Also, when suggesting that there is a cam timing issue with even more shaved heads, such as .080" off and using a belt that's a tooth shorter, why should I advance the camshaft a tooth to compensate and make the timing marks NOT line up. I wouldn't do that, a timing mark is still going to be right(note, the cam timing should be accurate/straight up at .080" off with a stock headgasket).
So, basically, in my experience, in the real world it doesn't make that much of a difference and if you are always shooting for the timing marks to be close to normal, it's fine. You can adjust the cam timing from there to suit your use and desired powerband, but it does NOT have to be set "x amount advanced" if you have "x amount shaved/thinner headgasket" to work "right". FWIW.