Syd Lexia wrote:

Someone still wrote a screenplay for it. With stage directions, scene descriptions, blocking, and whatnot.

Blocking is almost never done in the screenplay. It's taken care of on the set, usually prior to or during rehearsals. The only exception are sitcoms which often employ a fixed multi-camera setup that can require the screenwriter to lay out the positions of the characters relative to the cameras in advance. That's not really done in movies though.

I don't get the discussion about movies written by, directed by and starring the same person. First off The Green Hornet isn't even directed by Rogen, so this doesn't apply. Second there's plenty of good movies with one person filling all those roles. Some of Woody Allen's best films fall under this category. More recently Stallone directed, wrote and starred in both Rocky Balboa and Rambo. This seems more aimed at Seth Rogen than the fact that he is wearing several different hats. A sentiment I don't share; I like the guy.