It is, but it's pretty meaningless if you don't take into account the oppositon, who else was present/absent in the team at the time. And he was part of the team that rolled over to Accies, Thistle and St, Mirren at the end of last season.
Not saying that was his fault, or that he's not an important player - just that pulling out win % for a team based on a single player is too simplistic.