I think the big issue is they didn't completely think this through and were so concerned with making the game "predictable" without any chance that they didn't really maneuver with the system.
Then again my theory is early on armor wasn't really meant to be the "Second life bar" but rather a sort of small shield meant to break off eventually... Yet that changed early on in the design process due to Source Skills (meaning there was now a need to have large gobs of armor) and other huge flashy attacks.
