I'm not sure how having a whole roster, being paid only marginally more than your opponent's DH, is an advantage.
Not advantages relative to the competition, but advantages relative to the rules of the new league versus those of the NL. The results may (will) still be ugly, but he can give certain players more ABs in the AL, which helps him in assessing which players are part of the future. So, from a talent evaluation standpoint, I get what he is saying. I still hate the move, but there's not anything they can do at this point, so might as well make the best of it.