Trainer, RD housing...
 

Just curious...

Under - going over was causing some shifting issues with my Campagnolo Centaur group. Not sure why exactly, but the derailleur wasn't wanting to shift down the cassette. Going under solved it. *shrug*

I go over, but interesting about the shifting issue. My veloce doesn't shift as nice on the trainer and never thought the routing was the culprit.

47 views and 9 votes. I guess trainers are as unpopular as they seem!

How big are the retaining clamps nowadays that they would affect your cable routing? With my old Schwinn trainer from the 80's I've never seen this as an issue. Now rear spacing - that is an issue - I use my 126mm spaced Trek.