Hunh. That is really interesting. And it feels right -- there are too many similarities to SMG's current acting style and Buffy's withdrawal in s6-7. It could be more of the lingering burn out, as Sarah clearly was by the end of the show. I sometimes wonder if she really wanted to come back for season 6 at all. Maybe not a conscious thing, I have no idea, but I think you're right: the drastic shift in the character was less the writing and more Sarah wanting out of there.

If it is a case of burn out, then maybe her skills did get worse. Or hell, maybe she just wasn't that good of an actress. She was a soap opera diva before and without the melodrama or the tight writing to assist...

I feel dirty saying that. But she's a blond bit of nothing on my screen. Hell, even the crappy best-friend's-husband (who played Billy on Angel, btw) is doing a better job of creating a character and I would never qualify him as good at anything.