TrippyHippy
Hero
As I said before, the roles were DESCRIPTIVE; they described how the character was USUALLY played. Now, it was certainly possible to break the molds (something every edition but 4e did right; allow out of the box thinking) but the fact that they could be broken does not deny that a lot of people DID view the guy with low AC and high HP as the one to get beat up in combat or that the moment you find yourself with half the party in single digit hp or dying, the "gee, maybe someone should have played a character with cure light wounds" didn't happen.
It still doesn't matter if you use CAPITALS or not. They were not written into any books, descriptive or not, and were simply not there outside of some individuals imagination.