Re: Which advice is correct?
"The other is saying to keep the hands back as long as possible and let the ball get in on him more. Both say that their way promotes a more powerful hitting stroke. Which is correct?"
The second piece of advice more closely resembles what the pros do, although they aren't entirely at odds.
You do want to swing with a relatively short stroke. However, you don't want to just chop at the ball.
Also, in general you want to stay as compact as possible. Trying to hit the ball too far out front (which some people call "extending" through the ball) will actually slow down the head of the bat.
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