.

Although the excellent responses answered my question, I said I'd post pictures of the routing and cables in question. Unfortunately my laptop went kaput right after my last post on this thread, and my work blocks access to image hosting sites. I've managed to get my laptop partially running again (although it looks like it is going to have to go in for service), so here's the promised images. Hopefully this helps someone else with the same question!










This is the long run of it along the seatstay. I assume this is to protect the paint and maybe make shifting a little smoother.

Sorry for the size of some of these, I spent nearly an hour trying to resize them so they weren't huge or too small, but the laptop is slooooooow now and I need some sleep!

I suppose I should have taken a picture of the skinny stuff next to regular cable housings, but I took the above shots merely so I had a record of where each cable ran for when I put it back together. Hopefully you can see well enough in the images above how close in diameter to the cable itself the housing is.

I still need to swing by my LBS and see if they have some of this housing I can take off their hands. I should do that this week as my last wave of parts is arriving in the mail and the bike would be close to be going together if I wasn't tied up with school, work, and a couple of events this month. I'll report back in with how it went using what I get, when I manage to get to it in a few weeks!