I think the word you all need to remember is he said "consistently" Anyone who can shoot in the low 90's consistently is usually good enough to hit one 300+ once in awhile. perfect contact, wind at your back, public course with sometimes too hard fairways, downhill.
I hit a shot the other day, it was beautiful. I was thinking, "That's gotta be close to 300. Got to my ball, pulled out my iphone. Golf Logix GPS showed it was like 265. And I thought I cranked it. I think many of these guys aren't lying. They are high handicap players who don't really check the yardage on their drives. They are just estimating.
Don't get me wrong. I had a co-worker. Young kid. We'd go to the driving range at lunch. The back fence at the range said 250. He would just crank ball after ball over that fence. Straight as hell. He'd actually draw a crowd of guys watching him.
Then we'd go to the course. He'd still crank them long and deep . . . . . problem was, he was usually hitting his second shot from the trees. :>)