I think some of you guys are missing out on some key aspects surrounding Luke Shaw's performances. If you saw him at Southampton, in a LB role, he got freedom to drive at defenses from deep and could use his pace to get separation from defenders. However, since he's played as LWB in our system, his starting attacking positions are higher up the pitch. Hence, he is getting the ball much later in our build up phase where it seems like he's expected to take on the defender in 1v1 situations. So he has less room to run which takes away from one aspect of his game which I think coaching staff will work out with him over time.
The second aspect which is important to observe imo is that whenever Shaw has been picking up the ball, he doesn't have that many passing options around him. If you think back to how Evra was used last season, he was quite isolated on the left flank. With Shaw, it's a bit similar but not as bad as last season. One of Shaw's tendencies is to use his teammates as a passing outlet to run off of. If you look at any of his compilations for Southampton, you will find it's a common feature of his game. he hasn't been offered the same luxury in our preseason games thus far but he showed more signs of doing it against Roma which I would take as a positive.
There's more to observe as well but think that's enough for now on Shaw. I'm not worried about him at all. Having James as an option can't hurt either