I have heard nothing of the kind.

CPU's are very simple in this regard. Bus, Multiplier and Cache. Just set the multiplier and the bus speed and you're good. I have NEVER had to use a 3rd party utility to enable the cache on any of my ZIF CPU's (G3 or G4). I have had to do it on the Mach V systems though. Perhaps that is where some of the confusion is coming from?