Thanks Adam! I've edited things so we can see your diagrams in the post rather than link to them – much clearer. Your season structure explains what I have observed in some of our favourites which have major developments in eps 2 and 5 and a major crisis or two-part ep in the middle.
Thanks, Tim. It's fascinating one you start seeing the patterns. I've been known to watch a movie with my wife, and I'll suddenly say "Ooh, that was the first plot point." She just laughs at me.