Lead vocal on Black Hole and Rolls So Deep, more fucking with the Memory Man on Black Hole, backing vocals on Rolls So Deep (me high, Matt low).
Here's how we do vocals: about three hours a song. We start in the morning after a bit of noodling around, get the desk set up and the mic plugged in, then sing it through with the latest words, locating any problem areas or suggestions about the words or tune. We've been living with demo vocals and demo words for many months, and often there are little things about the demos that drive you mad. Now is the time to mention these and talk them through. Mostly, it's a case of trying out ideas and variations as we go. It usually becomes clear what's right and what's wrong pretty soon after the singing begins.
It's a weird quality that actually hearing the song sung has. You can know the song intimately, and you can imagine it exactly in your head, but until someone puts the tune on top of the music, you don't really know it. Some things seem like they would work perfectly in your head, but they turn out wrong when they come out of a mouth. Conversely, quite often a brilliant lyrical idea or effective little twist will suddenly pop up, and the song will be made better.
Matt goes into the booth and the singing begins, croakily and quietly, but it's good to record it all because you never know. We work through all the issues and try out suggestions, the end of which hopefully coincides with the moment of optimum throat-warmth. Then we'll run off two or three complete takes, which will generally be very good, with the occasional dodgy bit that you hope isn't the same dodgy bit as all the other takes. Then what always seems to happen is we take a little break and listen back, and then Matt says 'let's do a couple more', which is when you discover that we've peaked and pushing it any further will bring the fur and the fury.
Then, just to be sure, we listen to the takes from half an hour ago and find that they're great, at which point I go and sit on the couch and read one of Dan's hyperdull music technology publications while Matt does The Comp.

Of course, the trick is not to get total perfection. You need some authenticity to remain, to remind you you're listening to a human singing. Luckily for us there's usually plenty of authenticity left over.