In order to judge that, I've been spoiled for a few things, including the bar scene in the final ep. Having seen it (out of context), I can see one reading of it that most reviewers don't seem to have taken from it.
Spoiler for the Bar Scene in 823
It's pretty obvious that Dean and Castiel are talking at cross-purposes to some extent here, partly because of Dean's use of vernacular (although it's interesting how much better Castiel is at parsing and speaking that now).
Dean: You're boarding up Heaven, then locking the door behind you.
Castiel: Yeah, I know.
Dean: You did a lot of damage up there, man. You think they're just going to let that slide?
Castiel: You mean, do I think they'll kill me? Yeah, they might.
Dean: So this is it. ET goes home.
Castiel: *does not understand that reference*
I think we're obviously meant to read this as Dean does, as he's our viewpoint character in the scene. He assumes Castiel is going to close Heaven, and be inside Heaven when he does.
I'm not sure that's what Castiel is actually saying, though, especially given that he's looking resigned, but not sorry or anxious about how Dean will react -- Dean is always such a huge driver for him, so this seems a really weird calmness for Castiel.
So take away Dean's assumption about which side of the door Castiel will be on, and assume instead that Castiel intends to lock himself out of Heaven, along with any other angels who happen to be in vessels on Earth at the time.
Does the scene still make sense?
I don't have the full context, so I'm not sure. But I think maybe it does, especially with Castiel's re-wording of Dean's question, and his incomprehension about ET.
I almost don't want it to be readable that way, because it would make this the most perfect misunderstanding of all time. :)
This entry was originally posted at http://cupidsbow.dreamwidth.org/398983.html.