I used to have a large squad of players and tried to get them all between 42 and 50 minutes which was quite doable.
I did notice there indeed is a diffrence in full training or a few minutes less, however I change trainingtypes so often (to maximise effects of it depending on which players player how many minutes) that it is hard to exactly quantify it.
The way I am
guessing it is, is the following:
the ones who are not convinced much training is lost for minutes under 48 probably underestimate the effect
the ones thinking a considerable part of training is lost when 48 minutes are not reached are probably overestimating the effect.
In reality it will be somewhere in between. There IS certainly a loss, but it isn't THAT bad as many think.

The result of that loss however might be prety bad indeed.
(to explain this: say you loose only 5% training when you wuold have your player play 45 minutes, which obviously isn't that much. However if this happens consistently, your player who started out equal to your opponents for example will at the end of the season be clearly less good and may cause you to loose your game.
Ofcourse, if this caused your reserve player to gain more skill then your opponent's reserve because he waisted like 15 to 25 minutes every week to make sure his 1 player gets full training, this might balance things out again... Conclusion, I'm not sure which way to go would be best, except trying to get your players 48 or 49 minutes, which is VERY VERY hard.

)
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