GREAT CEASER'S GHOST!!!!!!!!! Amazing as it is TR I agree with you [for the most part]. What is the world coming to.
Batting average is relative to the competition. Not only the quality of the pitching as TR suggests but the quality of the defense. That said, .300 might be a good average for a freshman in any High School League. Likewise, .400 might not be a good average for a senior in an average High School League.
However, BA should not be the only thng examined by the coach/scout in his evaluation of a potential hitter. What is the players on base%? What is his slugging %? How often does he strike out per at bat? How many walks does he have? How many extra-base hits does he average per 10 at bats?
In other words, I don't believe BA average alone and not placed in context with other factors and stats means much at all.