[just another ref]

Originally Posted by billyu2

Could be, assuming there is contact; but quite often A1 pivots and continues to move (roll) anticipating a possible return pass. In these cases I would think A1 is no longer screening and the contact most likely would be incidental, would you agree?

This play would have to be judged on an individual basis. But intent is not the main concern here. Even if A1's movement is in anticipation of a return pass, if in doing so he hip-checks a defender and hinders his progress he can still be called for a foul.