When we first signs him, Allegri does play him as a trequatista, and a mezzala after that. Then Allegri quickly realise that it won't work for Juve, and change his position to regista. IMO that's a sensible move, moving Pjanic to deeper role to make the best out of his greatest quality: passing. The problem is his mentality, I feel he always afraid of losing the ball or misplace a pass, so he go for an easy, safe option to pass after all other's movement to creat space for him. I remember Allegri got angry with him after he pass the ball 5 metres to nearest teamate after 2-3 minutes of our team's movement to give him the ball. His mentality does improved recently, but it'll show whenever we are under pressure or pressed hard.