I saw this coming in 3.0. I picked up the 3.0 DMG and went, "What the #$!@!", when I saw PrC's. A chill of trepidation went down my spine, and I said to myself, "I hope they realize just how bad of an idea this is." I know what Monte was trying for, but the implementation absolutely sucked and with official no rules and guidelines to ensure balance things went to heck in a hurry. Of course, my idea of a 'bad idea' was something bad for the game. From WotC's perspective though, it was immediately clear that they recognized the market value of PrC's and they moved the PrC out of DM books and into player books. Really, that was the beginning of the end of the system. It wasn't long before I was hearing about various 'optimized' builds of multi-dipped synergized PrCs, usually either full-caster progression PrCs that ALSO got nifty powers on top of the already powerful Wizard build, or else full BAB progression PrCs that got the equivalent of a bonus feat every level rather than every other level. And from there, as the stuff proliferated, it just got worse. It was all I could do to hold back the tide.