I do have some thoughts on the accident. In short, the leader was at an anchor while the second approached the anchor, big avalanche, leader was OK, second unfortunately found dead after the avalanche passed. All the rope had slipped through the leader's belay device, so the second fell/slid the rope's distance while being pounded massively. The leader had two screws at chest level and was belaying off the anchor with a non-blocking belay device.
A few thoughts on this:
-First, I won't be surprised if the facts of this accident change with time. It's early yet, and things may not be as they seem. Mainly I'm sorry the accident happened, condolences to family and friends. This was an accident. Accidents are the worst thing about mountain sports.
-I highly doubt any belay device or configuration would have made a difference in this situation. It was a massive slide likely with enough debris and force to kill anybody in the way. But a smaller slide or a smaller slide that also hit the belayer could have been fatal to the second not due to the trauma but due to the belayer being unable to hold the rope while he was being pounded, and the second falling the rope's distance as a result. An auto-blocking device would be a better idea.
-I don't think belaying directly off the anchor with a non-blocking belay device is a good idea. Especially if that device, as is reported, was likely at or higher than the belayer's waist. I can't see it being easy to hold your arm up to generate sufficient friction to hold the fall, as would have happened in this case. I can hold maybe 50 pounds over my head with one hand for any length of time, and that's in the gym with a very controlled weight directly over my head. Not a rope whipping around with all sorts of weird vectors. The moment the belay rope isn't pulling "up" on the belay device is the moment it starts sliding, and is then more difficult to hold...
-If the brake side of the rope is less than 90+ degrees off the loaded end of the rope then there just isn't likely to be enough friction to hold a high load. If the two ropes are parallel very little friction will be generated. Even a top-rope load can be hard to hold until the rope is pulled into proper position by the belayer. Anyone who has held a climber from above while top-roping for any length of time with a non-locking device knows that it takes some careful positioning of the rope to make this comfortable. I don't think the belayer has much chance to hold a more powerful fall with the device above waist-level, and while pulling "up" on the rope. The belay device would have to be at knee level or below to be effective, then you could pull "up" on it.
-The solution for me is straightforward: use an ATC Guide or some other auto-block belay device when belaying the second off a solid anchor. In Canada and Europe this is the common method of belaying the second, but it's still less so in the USA for some reason. This is changing, maybe due to international guiding standards, but I still see a lot of people using a non-blocking belay device for the second when it would be far more suitable to use an auto-block to do so (90+ percent of the time while ice or rock climbing, less so with alpine climbing).
-If you're going to use a non-locking belay device for the second then it should be on your belay loop. Not clipped to the anchor, not extended off the anchor with a sling, but on you. That way you'll always know which way to pull even if you're getting pounded, upside down, getting pulled off the stance, whatever. There have been several bad accidents where the belayer was injured seriously but held the belay when it was off his harness.
Again, I don't think it likely would have made much difference in this accident how or what type of belay was being used, the situation was just off the charts in terms of power and violence. An auto-blocking device could even have generated enough force to blow the primary anchor and kill both climbers; this sort of situation is just drastic. I had one large slide go over my head while in a cave once; even while totally protected I couldn't breathe, couldn't think, the power was just insane. But I do think there are a range of situations below the magnitude of this one where an auto-block belay device rigged to a solid anchor would be a better choice and might might make a big difference.
There are situations where belaying the second with an auto-block doesn't make sense, but part of being a good climber is understanding enough to recognize those situations and build your belay system appropriately. Most of the time when I use a belay device for the second straight off my harness I do so because I'm concerned about the strength of the belay and want to take as much force as possible on me and my stance. I keep the rope very tight in this situation and recognize that I'm doing something dubious, or at least well outside what is commonly "safe."
There are some other things in this story that bother me precisely because I've made the same bad calls:
-Not being aware of the avalanche hazard. "Hey, it hasn't snowed much, should be good." This is not a good assessment of avalanche hazard. Read the avalanche forecast, look for the signs, understand enough to make a call.
-Assuming there is no hazard just because "this area has no hazard." Almost every ice climb I've ever done has enough snow above it to be a hazard. Snow is heavy.
-Not being able to see the top of avalanche terrain while moving through it (cornices, wind loading, etc.). If you can't see the wind loading and terrain above you then you have no idea what's going on.
-Not paying attention to the obvious signs of instability (debris piles on the route, etc). We all want to go up, and it's easy to rationalize things so we keep doing that.
-Not thinking about the terrain trap nature of ice climbs. This has killed at least two friends; even "small" slides funneled into the wall of an ice climb can be lethal.
Right, not sure why this story hit me so hard but it really did. Maybe because I can see myself making some of the same errors. Again, the facts may change, and this is absolutely not meant as a critique of the accident at all, just things for all of us to think about as we go ice climbing.