In reply to ElvisMax1:
> Sounds like a nightmare worth avoiding. I'm fairly new to climbing multipitch routes. Lower grade and intermediate routes, although easier going up, with more and larger hand-holds, etc, strike me as being more likely environments for rope jams. I don't want to sound like a chicken, but, if you were looking down a route that looked potentially troublesome, would it make more sense to abseil down with just a single 50 meter rope and avoid the problem?
A single 50 meter rope isn't going to get you very far on a big route, and might not be long enough for some abseils. The main thing is to take extreme care in retrieving abseil ropes, making sure the rope doesn't go into any grooves etc. Flicking it as necessary to keep it in the best line, and flicking it over lips of overhangs etc. Make sure the other rope (going upwards as you pull) has not got any kinks in it. Often both climbers will be pulling the down rope, if there is significant friction at the top, to make it come as smoothly as possible.