I guess when I think really gifted, I'm thinking of kids who score in the very top (145 and up maybe) and I do think that not a lot of average (even prepped) kids score there.
I'd agree that prepping an average kid into looking PG probably isn't going to happen and I don't even know if group tests have ceilings that high anyway. I am think more along the lines of it being possible for an average or slightly brighter than average kid to look mildly gifted with prep or even the right amount of convergent thinking on a group test.
