As we all know, Dom 3 is, overall, extremely realistic (e.g. weapon length).  This is how 
real magical armies fight.
However, it seems to me that fatigue-causing, at least, is not 

  If I have a great big weapon and plonk it on a little guy, how does it make sense that he gets the same amount of fatigue with the same effects as a giant brandishing it?  Why doesn't he get more tired, or have a lower tolerance than 100?
This has bothered me for a while now.  Am I missing something?  If we wanted to handle fatigue as realistically as so many other factors are, how should it be done?