In reply to lmarenzi:
Thanks to all of you who have posted on this thread, Are You Confused At The Belay?, which now seems to have run its course. It was fun to exchange opinions on some things that I had not thought would come up and hear from some people who I would not have expected to hear from, and I have learnt a lot.
The original intention of posting the link above was to talk about how to thread the anchor on single pitch sport climbs. It was a gimme/slam dunk/open goal question, since the technique shown in the original video, and the one posted subsequently, are obviously wrong. The climber in both becomes detached from the rope. That is confusion about what roped climbing is. To avoid potentially dropping the rope the climber then clove hitches it to the nearest quickdraw. The problem with this is that it implies that the climber is no longer on belay, and is like a written invitation for the belayer to take his eye off the ball (and have an emergency pee, flake the rope or put his shoes on) at just the moment (or 30 seconds before) the climber at the anchor is going to rely on him, and only him (or her), for his safety.
There is one last point, which is that some insist on going through the trouble of rethreading your figure 8 or bowline rather than clipping into a twist lock crab before lowering. If you are guaranteed to be simply lowered, then there should be no objection to the twist lock. I have done this many times to save time. However, in single pitch sport, time is not the factor it can sometimes be on the hill and every time I have done it I have felt a bit funny. So now I always re-tie the knot - personal preference.
On this last point I think its worthwhile expanding a bit. The obvious flaw in the video above was spotted by quite a few posters, but I admonished them for being cautious. I think its good to be cautious when actually climbing, sometimes very cautious. But on a discussion forum, and when coming up with systems that are as safe as they can be, I think its time to let your deepest paranonia run riot.
For example, I sometimes climb indoors at a wall which is no more than 12m high. I have a 30m rope. When I climb I always make sure that the dead end of the rope has a knot in it to prevent it pulling through when lowering after climbing. Of course at the wall, the rope can't pull through because the rope is easily long enough. But I want the system I operate to be as safe as it can in all situations. When I get out to a crag I want a short rope accident, that has cost many lives all over the world, to be as unlikely to happen as possible.
Reading posts and opinions on the internet is a good place to start when planning your personal safety in the hills. Reading books too. Ultimately the decision and the responsibility is yours, and you would be a fool to believe everything you read. Be smart on the ground, figure out the safest system, and go. Being slick with safety is good, but only if the safety is sound in the first place. Even the best system will fail sometimes, as fatigue, complacency, misunderstandings and loss of concentration take their toll.
Believe me, in my time, I have threaded the belay much, much worse than the video above. Nevertheless I think I have a clear idea in my head now, which I think maximises safety. Until you have a clear idea of how to get down, its probably best to not venture into single pitch outdoor sport at all.
For the sake of completeness, the manip I was taught a while ago now is to put in a draw at the anchor, clip it, clip into the upper bolt with a twist lock on a sling, put a twist lock on your belay loop, pull up some rope, tie rope into twist lock, close it, undo your knot, thread the bolts from back to front and tie back in. Then get your belayer to take hard to pull you to release the twist lock and let him lower you. There is a variant if the rings on the anchor bolts are big enough to allow you to pull the doubled rope through.
You might have a safer way? Let us know if you are sure ...