DMSMH was perfect, it sold, so why change anything. If he was getting money for it, what could be more important than that?
Anyway he continued to sell it after he thought that dianetics wasnt the answer, why did he do that? Probably because it still brought people in thinking that they could go clear, easily and cheaply. It sounded fairly plausible as a technique.
Did Ron actually ever go back and correct anything? He preferred to just keep spitting out more and more stuff, just saying it was now even better, with a little comment about how it wasn't quite taped before. Hell--KSW, Tech Degrades, and 'there is no such thing as old-no-longer-used tech'. High Crimes and all that. He wasn't a guy big on reflection or correcting himself--just kept barreling ahead. No way in hell he'd put a redact in a book about ANYTHING, let alone telling folks they couldn't get auditing now, or that "the answer" was no longer "the answer" for everybody. Dianetics was there, as things evolved, just to get meat into the Scientology machine. Books Make Booms, baby!
You are so right, that's why it was so hard to understand, even KSW had a few inches of old org board routing to have too wade through before the real meat of the policy. None of that was necessary to actually understanding anything. So you have to learn remimeo etc etc etc before you even get to the bit where he says he never makes a mistake and everone else are bastards.