I liked that conclusion, but I think it would have had the same effect on the audience and the characters if it had happened a few episodes ago. But I'm just glad that particular plot point is done with now.
Sometimes I think Shane's got the right idea concerning survival and whatnot, but he does go over the top quite a bit - but some of those melodramatics while in the middle of a much more pressing zombie apocalypse would probably send me over the edge too.

Was very annoyed at him for ranting on about how all the zombies have to be put down, they aren't people etc.
Spoiler only to freeze up when confronted with one of his own group.
Hershel's face during that whole scene made it for me though. The man looked totally broken, and it was the first time I found myself sympathising with his situation, even if I don't agree with his methods.
Not quite sure how being lowered into a well with a fat zombie has any relation to Portal though. Left 4 Dead would probably have been a better reference.