He said something similar upthread here. Of course the word "slab" has specific avy meanings, likely not his intent. As I try to picture what he describes I think it might well not meet the definition of an avy, or at most be some variant of a small point release. The big as in potentially deadly problem here obviously is his certainty that a slope that steep can ever have "zero avalanche danger ... Zero. None" as long as there's snow on it. Maybe the risk truly was trivial that day but I haven't seen him describe how he arrived at that conclusion. He hasn't even said if he read the MWAC bulletin and extrapolated from that for King Ravine, much less whether he did any classic stability assessments e.g. firing off a few rounds at likely trigger points.