That kinda sucks, but oh well.
How would making it linear be bad though? If someone played "a few minutes" (3), then they wouldn't get a significant amount of game experience - they'd only get roughly 7% of optimum training.
I guess I'm not seeing the negatives of making it linear, especially considering the fact that we as managers can't exactly dictate how many minutes our players get.
Friends Do not Let Friends Play 2-3 Zone