Yeah, I can see it. Armor isn't exactly the best sort of thing to be fighting off magical diseases in. It seems a lot more of a 'This probably is using up energy you could be using to not get sick' thing.
yeah, i actually don't have a problem with this. Its kind of like if I have a cold, I don't usually go the the gym to lift weights. I'd rather spend my energy on getting well, not getting bigger muscles. Is the armor check penalty a perfect fit for disease resistance, well no but it isn't a stretch for me either.