I marked my single rope so I can find the middle when rappelling and also to give my belayer a warning when I'm on a route of unknown length.
I am going to purchase a set of half ropes soon for some Mixed/Ice Alpine Routes in the Rockies and am wondering if it is a good idea to mark the middle. I'm only wondering because rappelling you just tie the two together so no need there and if doing running belays and making your own belay stations in an alpine setting a middle mark warning to the belayer doesn't seem to be of concern.
Do Half/Twin/Double Ropes get Middle Marked? If so, why?