hmm... i wish i hadn't listened to some of you guys lol.
i bought an 18 yo today worth 1,6 million and turns out he is the worst trainer in my team. Always get exactly the amount of training that is the average (30% for Practice Match, 20% for Cardio, 10% for Stretching)... meanwhile, my older players, up to 22, always gets more than 30%/20%/10%.

Turns out the guy who should be getting great training is the worst of the bunch. so now I have no idea why this guy was worth more than other 18yo's his age and as good as him :S