It does veer from the premise of the 'list' but that is good; the show is about some pretty strange folks and giving a deep background on Crabman ties up all the peeks we've been given since his introduction and makes me want to go back and view the series all over again. I wonder if this episode was in concept all along.
Danny Glover is wonderful and effective in his role, the spy tricks used are really over the top and its laugh out loud funny (or funnier!) as 'Earl' has been. I don't see the slow slipping here, and to compare it to the fall of 'South Park' is apples and oranges. South Park has never been as inventive as 'Earl' in script or in visual style, and the show doesn't rely on bathroom humor to be entertaining.
I'm emailing friends and telling them to look this one up, its one of the most inventive 'Earl's I've seen. This one has me interested in episodes that I haven't seen already, causing a re-ignition to my interest in the show. I'll be watching, again!