First thing I noticed is that they fall into the all too common "throw a part at an engine, dyno it, then throw another part on, dyno, etc".
They should have done back to back cam swaps with the same heads, and tested the same cam with different heads, etc.
On top of that, doesn't seem to be much of a daily driver motor at 92 octane. Not to mention the fact they were using it with old school heads, when it might have made more power with 89 octane (for instance) with the vortec heads.
That's what I see from a cursory skimming.