it depends on how the team is constructed. If a player can mash the ball, but clearly cant play defense (and is hurting his team by doing so), then DH is a perfectly reasonable spot for that player on an AL team, regardless of age. Thing is, with all the new info available to teams, teams are realizing how important defense is. The idea that a player shouldnt be a DH when he's young because other teams havent done that in the past is no reason to not do it. BTW, In the last three years, the team with the best UZR in MLB got to the World Series and the last two years the team with the best UZR in MLB won the World Series.