Yeah, Feller was the original flamethrower when he first came up and was young. Wynn, Lemon and Garcia were all hard throwers too. All pitched for MANY years. Don't know about Houtteman.
If pitching year-round from age 10 is the problem, you'd think the bright minds out there would take steps to remedy that.
As a laugh, true story that Feller, from Van Meter, Iowa learned to pitch in the '30s by throwing at a bullseye painted on the family barn. The velocity was in his genes I guess.
The
original flamethrower was Walter Johnson.