The aim for the flag mentality isn't just a post ProV1 thing.
I asked Jim Colbert about his strategies, etc. (circa 1983-1984, perhaps his biggest year on tour) Sort of like my convo with Lanny Wadkins about aiming on the tee shot (answer, well, the middle, duh) I asked Jim how he approached his approach shots. And, the answer was, always (almost) aim at the pin. He figured someone was going to be hot any given week and would aim and successfully get close to the pin to shoot a low score. So, he did, too.
When asked what happened if he aimed at the pins and wasn't on his game, the answer was, "I lose!" But, he figured he probably would anyway. Again, he had the mentality, even as a grinder, that you went out there to win. Purses were big enough back then, but even so, it didn't seem he was playing just to make a cut and get a check.
Separate topic, and I don't know if there is any supporting data, but are Tour greens really that flat? On the TPC courses (which we presume are custom designed around the players wishes) I have played, the greens really seem to have been quite contoured, not just the supposed 1.5-2% everyone here seems to assume. I guess I could order the yardage and green reading books for PGA Tour courses to find out, but maybe some has a few of those color coded charts where we can see? Maybe Tom Doak can chime in on Memorial, how much contour and what were the reactions?