I kinda see what you are saying, but it's better that AMD continues to gain marketshare. The reason? In order to allow even more competition.
Part of the reason that Cyrix barely exists and that IDT and Transmeta couldn't compete is Intels huge mindshare. If AMD were able to split the market 50ish/50ish with Intel, that would likely destroy the Intel mystique. As long as Intel dominates the market AMD is in danger of extinction and companies such as Cyrix or any potential new company will remain so far out of contention that they won't be able to survive.
As for AMD raising prices, well as long as they continue on their current path of marketshare gains, they really have little to gain from large price increases. Increased sales volumes and thus increased revenues/profits will keep shareholders happy. When marketshare plataues(sp) , that's when price increases will become a concern.