As
@bosnian_red explained, De Gea is "average" over the course of the season. He is VERY GOOD currently. This is the problem, people in general tend to remember his last few games and then they read that he's "average shot stopper".
Just a few weeks ago he was on PSxG -0,1 and now he's aleady -0,05, what means if he continues on current form he is likely to get into top5 shot stoppers in the league - sounds about right?
PSxG is a nasty parameter because a few bad games (City, Brentford) make you look very, very bad as a goalkeeper. Now he's getting back to the "average" line but with clearly positive trend.
See this:
But De Gea had a lot of very good games in the last 1-2 months, so he might be reaching the top 5 shot stoppers in the league already if it wasn't for Brighton and Brentford. But why would we be excluding those games to calculate the average? This is the moment his experience was needed, he and the team failed and this will be reflected in overall season stats. Being great on one day and poor on another is exactly what "average" means, it doesn't mean he's average every game.
Now getting to those tables shared by John Harrison:
There's a couple months difference but you can still see the same names on on top 5-7 and the same for bottom 5-7, what would indicate those models are not that far off each other.
You're referring to tweet from June 22'. In November Harrison labeled De Gea "average". Again, he clearly improved after World Cup.
Exactly.
Anyway, the point is not to prove he's average shotstopper. Considering De Gea is clearly poor at preventing shots and distribution (whatever data, eye test or any other method you use to judge that), he really needs to be TOP shot stopper for United to make it worth sticking with him next season.
To be honest there has been plenty of reasons and evidence presented here and in other threads to support the claim that De Gea should be replaced in the summer, while the only reasonable contr argument is that we might end up getting worse GK than him. That doesn't convince me at all. Not if we are aiming high. And definitely not if we're looking long term.