this has probably been discussed a number of times in the help forums, but as you mentioned it took you here, I might as well try to answer it here...
My personal view is this:
every time the player ages, there will be a decline in trainingspeed. So from what age on? right from the beginning...
until when is he worth training? I'd say 21 for sure, maybe up to 23, but no longer.
I have been keeping players from their 18 and 19, into their 24 and 25 now, and you realy notice they slow down at 21, but still train, once they reach 23 it starts to go slow, once past 25 it takes ages.
I trained as much players as possible all the time, so if you focus on just a few, it might still go a little faster, but if you realy only care about progressing players, and less about game results, I'd say sell them when they are 20 or 21, that way you'll get the best out of training, and at those ages they are still worth a lot.
Maybe others have other visions?
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