Im not surprised. Thing is that his strength arent the 'classic' technical skills a la touch, dribbling, general flair. He lives off his work rate and pace in combination with a very good anticipation and off-the ball movement, that are bringing him into situations where he can score (and use his strong finishing with composure).
Thats also why he doent work too well on Bayerns flanks, where he is acting as the Robben replacement currently, b/c he doesnt have the same skillset as the dutchie. He needs to be passed the ball into space, where he can run in and score or alternatively pass the ball around. His movement isnt only helping defensively but also creating space and confusing the opponents.
SO while he works better behind the striker in munich, he works very well on Germanys flank. Sounds strange, but is due to the fact that germany builds up differently, i.e. via Özil through the center (where he can play the throughpass on the storming Müller) or the left flank (when Özil drifts there and creates space in the center for Müller to run into).