So of all the high school leavers, the high achievers get into a Graduate program? In common speak that would make those high achievers above average wouldn't it?
You can't just stratify the sample into "people competing for a spot in a graduate program".
I'll ignore your second and third paragraph because p2 agrees with my PoV and p3 is just the usual "when I did it pre-nerf" blather thats irrelevant to what I said.