I can hardly belive that if you have all your players play about 65 minutes they all are proficient in GS.
I had players playing 44 minutes and have proficient game shape as well, and other players who played 55 or 63 minutes who had strong game shape, or even respectable...
I think it is prety easy, if they play enough minutes (and not too much) they can be between respectable and proficient, no matter exactly how many minutes they get! So giving up a number to aim at is not right in my opinion.
I'm prety sure that a player who gets 48 minutes every week has as much chance of getting the highest GS as a player who plays exactly 65 minutes every week.
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