These are the sort of detailing videos I find more informative than the torture tests, blatant paid product placements and the egos that plague this corner of YouTube. While I know Sidney is a brand ambassador for TRC and P&S, look past the use of those actual products and there is plenty to learn here from a technique point of view.
Before YouTube, how did people learn this sort of thing? From an employer? A training course? A family member? Reading forums? Trial and error? I suspect for most of us it was the later. Personally, I got none of my detailing skill from my father, his idea of a clean car is to leave it in the rain. YouTube was not a thing when I started detailing in my mid-teens. I also wouldn't have had the confidence to attend a training session, let alone find one being offered. I think the first time I sought further information beyond what I had fumbled through myself was back in early 2008 at age 21 and waiting for my brand-new car to arrive. After searching the internet, I stumbled across the detailing section of a local Ford forum, reading posts written by a semi-pro level detailer. It only built and built from there. As it happens, I'm now that semi-pro providing information to others.