I can understand him not breaking through into the Arsenal first team at the time, as they were Champions League and could pick and choose from a very talented pool of forwards. With us his competition was much more limited, the likes of MacManaman and Gardner. And when it came down to selection, Pulis preferred the Gardners and MacManaman's. To me at least, it was obvious that Gnabry was in a different class.
I can accept that some of the blame that he didn't establish himself may have been down to Gnabry, but only some. When you have a manager playing for 1-0's or even
0-0's, by-passing the midfield, expecting an attacking flair player with his talent to spend most of his time covering his own right back deep in his own half, I think I'd lose heart.
Obviously the manager sets the tactics, and so it was a mismatch. That's part of what you buy into when you appoint a manager. Pulis can only play one way. He picks players primarily for their defensive skills, even the forwards.