Sure, if you don't account for crappy low A defense or his high BABIP. Billy Hamilton, as a LHH, hit .339 on ground balls FIELDED by the shortstop or third baseman this year. Dude is fast. But that is never going to last. He hit .294 on balls fielded by the pitcher. Never going to last. He hit .429 on balls fielded by the catcher. Never going to last.
So you can't just extrapolate his second half Low A numbers to the MLB level, because they were achieved in a way that simply isn't going to happen at the MLB level.