I have done it when wet and of course it is more challenging...I really don't have strong feelings about this either...no one is going to see the bolts, there are good arguments for and against....and I think most responses I've seen are for...certainly I respect that...maybe if it's really slick I would use the anchors, but having done the descent a number of times now, I doubt it...just not necessary...
and it does take some of the shared adventure away from the experience...you know how when you've done a route that involves a little bit of something, whatever that may be, and you find out someone else has also done the route...I think with Old Original, for example, part of that experience is getting back to the ground...
I would argue that if one wanted to put energy into anchors there are a number of anchors that are set so far back as to cause ropes to get stuck or not pull...for example the top of Cuidado as we've talked about in the past...the top of Mission Impossible is another one that comes to mind, lots of examples like that...