(1) If x is morally wrong and S freely does x, then S is blameworthy for doing x.
(2) If x is rationally optimal, then S is not blameworthy for freely doing x.
(3) Therefore, if x is morally wrong, then x is not rationally optimal.
Skorupski (1999, 170) claims that we can derive (3) from (1) and (2). Intuitively, this seems right, but how exactly is the derivation supposed to go? My logic is a bit rusty.