A 100% fit Jack coming back will elevate the performances of those around him. He will be the focal point of the opponent dragging opposition players towards him creating the space for the others to thrive.
It's something to work on for sure in the transfer window. Imagine having 3 or 4 consistent attacking players. Losing Jack for a few weeks will not be as bad then.
Still all to play for. We are on the right track.