In reply to Erstwhile:
"The forecast risk was 2 to 3, so this kind of event proves that estimations of risk are currently not very reliable, which has been the case for the last couple of weeks (since the first significant snowfall this winter)."
I think they are right to pick you up on this for a number of issues.
1. By saying not reliable you may encourage people to not use them.
2. I think you are misunderstanding what risks are. Even a category 1 rating can still lead to avalanches, 'generally safe' 'not likely' does not mean they won't happen. We can put the odds in our favour but where you have steep slopes and snow there is always some risk.
There was a case a good 15 years ago of a Scottish guide and his clients killed, the aspect he was on, the area where he was, was a pretty safe area in those conditions but they can still and do happen.