Dogtooth slack country Fragile Cornices

I roped up to assess a large cornice in the Kicking Horse slack country on the "Wisdom Tooth" As I was approaching the edge the cornice failed and pulled back 10-15 ft, 10ft deep and 50ft wide creating a size 2.5 avalanche composed mostly of cornice debris and entrained snow, 20cm crowns visible on the edges of the debris in the fans, no deep step down noted. Avalanche ran 500m over a cliff and into a north aspect. If I had not roped up I might not be telling this story, my t-slot anchor got a good test. Otherwise only 1 size 1 skier triggered avalanche 20cm deep, 5m wide and 40m long observed today.