You're just being willfully contrarian. You know pitchers can add to their value by being a competent bat. Zambrano added like 1.5 WAR one year, and Lester is literally the worst hitting pitcher in the game. You don't see how that lessens his value in the NL? For a good as a pitcher he can be, he continually shoots himself in the foot with pretty much every other single aspect of NL baseball. Zambrano is a clear outlier and a really stupid comparison point. Lester is obviously a shitty hitter even by pitcher standards, but ultimately most of them are just varying versions of the same shitty hitter.