Yeah. That will help with him believing that Draco is something other than evil when he finally begins to see what's going on with him.

Part of Harry's talent is just inherent; I think that if his talent on a broom can be, this can be. But I'm also taking the view that training with the DA helped a lot, too. After all, Luna and Neville were part of a group of six students that held off multiple adult wizards. That's some heavy training.