Wassat, I hear you thinking? It's this - isn't it nifty? But of course, that only works if you have your tags organised, and I... didn't. So, I went through my tags and renamed them into something that would look pretty when the code went live. (Heads-up to anyone who had any particular tags bookmarked or linked.)
Then I figured that there might be some improperly or incompletely tagged posts in my journal, so I went back to the beginning and started checking, post by post by post.
24 hours later, I have added over 70 formerly untagged older drabbles and drabblesets (some over 2000 words!) to my btvs:s/x:misc tag (and if I have to explain that acronym, you don't know me at all. *g*)
Lesson for the day: Sometimes, a touch of OCD can be a good thing. :D
BT Update: They're still a$$hats, but finally, after 24 hours or so, the illegal, immoral cookies from hell stopped appearing and messing up my ability to browse. There is still some lag time between my clicking a link or typing in an url and hitting 'go' and actually having the page start to load, so I may still be being rerouted through the Webwise servers, but BT haven't contacted me at all to discuss the matter, despite promises of <24hr responses to my emails. I'm still looking for a new ISP. And I will be complaining to someone further up the foodchain.