There's no substitute for velocity that's for sure. Saying used to be "we can teach a guy who throws 95mph to throw sliders and changeups, but we can't teach a guy who throws 85mph to throw 95mph. I'd have to say anymore that you're correct.
One thing that baffles me to this day.....how can everybody throw 95-100mph today, when 30 years ago a guy who threw 92mph was considered a hard thrower? Only thing I can think of is that back in earlier days, the radar gun picked up the ball a few feet after the pitcher let go of the ball, maybe almost half way to home plate. Today I believe it picks up the ball right out of the pitcher's hand. Big difference.
Can't really comment on difference in radar guns, but I do think that the kids on average are just bigger today (with or without steroids) than 30 years ago, and bigger = more velocity. Is it better mechanics? Personally find that hard to believe, given some of the funky deliveries that I see and the Tommy Johns that are performed.
You must be younger than I am, "earlier days" for me was pre-radar, LOL.
