I was training Physical and my driver maxed stamina = 20 after that i was keep training him to lower his weight but sometimes Stamina pop up maybe 2 or 3 times in a row. Normally when is stamina message is "+1 Stamina" or is "-Weight" for my just say "Stamina" with no Effect. Driver is at Reserve but Stamina didn't drop 19 as i am Training all the time Physical.
Maybe just have drivers always lose weight every time you press on the training button regardless of what attributes you are training. How about weight loss between 0.1 - 0.2kg per training session (button press) the actual amount being linked to the ability of the Doctor.