I disagree with that guy.
Number one, he says that "compression cannot be adjusted when sitting still, without riding it over a bumpy road".
Not true, it IS an easy adjustment sitting still, but just like rebound And preload, you will not know until you ride it, and you will always make some adjustments to all after.
Number two, he says "the rear rebound should snap up and not settle".
Not true, as then you will have a pogo-stick that will bounce hard over every bump.
Properly set rebound should allow you to grab the tail, lift up, and have a little slack, an inch or so, to move up and down, otherwise...pogo-stick.
That's why I recommended Dave Moss, a real suspension guru, not just some youtube guy with a bunch of views.