WEL,, I think there might be a little diffrence.
In the U21 it shouldn't be to hard to find a second player (of any age) that is about equal to the U21 player, and so rotation of the players and thus dividing minutes nicely shouldn't be a big issue.
for NT players, they often DO exceed the other players in the team, and the urge to let them play more minutes is bigger.
I know fully well nobody can ask managers to have their best and most paid player play fewer minutes.
All I try to do is to eliminate that pesky theory, that unstopable idea most have about how many minutes players should play each week as a MINIMUM, to get a good GS.
And I am glad you also noticed that closer to 48 is better.
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