I don't know why people conflate "chasing the lands" with "seating depth doesn't matter". Seating depth does matter. It's chasing the lands that is stupid.
As to Eric Cortina; there is no denying the man shoots well. Doesn't mean he is smart. Try listening to him explain a complicated idea you quickly realise he is a bit out of his depth. It was quite painful watching the podcasts between him and Bryan Litz. That said, he can shoot and, judging by his scores, can react to wind changes better than most.
Some things that he preaches is quite misleading. Case in point is the time he walked in the pits and asked everyone there if they full-size or neck-size. By far the majority answered "full-size". What he neglected to add is that all those shooters have custom chambers designed to minimise the amount you have to resize cases. Doesn't matter for people with target rifles, but sucks for the new guy using a Lee Enfield with a generous chamber.
What really iritates the living crap out of me is that, contrary to some comments above, he doesn't share his all his knowledge. He admitted that as well. If he knows something that no one else does, he will keep it a secret because he wants to win. Is he an asshole for doing that?
Bottom line I can honestly say that I have not heard anything from his videos that I have not learnt elsewhere before he became a YouTube sensation.