But that's my point. If a player is strong and has 100 minutes this week, his "true GS" is going to be respectable or average at the training update. Training GS will typically help that situation, keeping him at high respectable or strong.
By contrast, if I get my players 60 minutes a week, week-in and week-out, their natural GS is going to be medium strong or better pretty much all the time. Training GS will do me jack diddly.