I know this is a can of worms as evidenced by the thread less than a year ago in the California forum which explored the same topic. I recently climbed North Palisade with a friend and we opted to climb the 4th class crack/face just west of the chimney. My friend brought a 8mm rope of some kind, twin or double, and a very thin rack. He led way off route and we ended up zig-zagging all over fifth class terrain. As he was belaying the rope nearly sideways from me while I traversed an overhanging block with a pendulum fall as a consequence I wasn't feeling too confident about this line. We never fell so it was a moot point but I have to wonder what peoples experiences are with using thinner twin/half ropes. Has anyone fallen on one as a leader or a second when it was used as a single rope? Ever damaged or cut through one while in the mountains?
What kind of rope do you climb on in the alpine? I've had a 60m Beal Joker rope that I intended for climbing mountains for the past year but it has yet to see any action at all. I'm curious as to what benefit a pair of 30m twin ropes would give me over the Joker. Wouldn't they weigh just a bit less, rap the same distance and limit a pitch to 30m?