User blog comment:Zathronas/Analysis by an author: What did I miss? part 2/@comment-10380701-20140122000339

One tiny speculation was that Ozpin had a flying machine that he uses to get to the temple.



That or it's a walk in the park for him. I mean, as you said, the Grimm are effectively underpowered compared to first year students. Ozpin is the headmaster.