I think we saw how it could work well in our good run, tbf.
Gylfi is key to it working because of the press. And in fairness, in the earlier parts of the season he was dropping off and getting the ball in between the oppo box and the halfway line and looking to play from there. That's where he creates chances from, that 30-20 yard out mark.
He isn't doing that lately as much and when he is he has been sloppy more often than not. I'm not using his positioning to excuse his poor play.
But, as you say, we don't actually play him as a midfielder, until we go 1-0 down and Silva panics and does that ludicrous thing of throwing all of our attacking players on so we're just left with a gap of 30 yards between Gana and the rest of the team.