Rules-of-three, WotC píše:
During the development of the 4th Edition system, we discovered a hole in the system math: Characters who added their ability score modifiers to their ACs began to outpace the AC of characters who wore heavy armor. (Yes, in retrospect it's obvious; we spotted it when we began to playtest at higher levels.) Clearly we needed heavy armor to improve at higher levels. Ideally, it should improve as fast or faster than a rogue could pump his or her AC with ability score improvement. Since the concepts of "masterwork" and "special materials" were basically still untouched on the shelf, we decided to marry them up with the improved heavy armors that were necessary at paragon and epic levels. That's how we wound up with the armor system you see in 4th Edition.
Poslední týdny, co vývěska Rules-of-three, to perla. Člověku se chce až brečet. Ale potvrzuje to v zásadě to, co se traduje už dlouho. Čtvrtá edice nebyla pořádně play-testovaná na vyšších úrovních, spousta matematiky tam se sype. Zde exponát č. 37.