I began diving in a hogarthian style around 1994/95 which was a good few years before DIR even existed. DIR cherry picked the style of diving that I used
DIR has only really developed one new idea that didn't exist in hogarthian diving and that is stage marking. That is probably DIR's best idea to date.
The most useless idea they came up with is their sidemount system which really shows a lack of understanding of sidemount caving. It's there so they can say "we have a system" rather than actually developing something that works.
If I was still diving OC then I'd still be diving hogarthian. I don't know if I'd ever become fully DIR though.