Has nothing to do with it. All their trainees just happened to have the same high sublevels at the same time as that training date.
ex. Player A, Player B and Player C all have HA x.9 DR x.9 JS x.9 and then 1on1 forwards is trained. 9 pops, 3 players. More is even possible with the 10% cross training, but that would be a small miracle for that as well to be a skill at x.9
If you remember me, then I don't care if everyone else forgets.