Quick report
Late in the evening on Friday January 29th 2016 a storm hit the Wasatch range starting out warm and brought with it a high elevation rain/snow line. This rain buried and preserved surface hoar in sheltered locations in Broads Fork.
There is 8'' of new snow sitting on top of this layer. It was found on a NNE aspect at 8400' in elevation HS - 140cm and ECTX. I felt the crust up to 9000' but did not travel any higher.
Even though I got an ECTX here, I would expect different results in wind drifted terrain or where the new snow was deeper - I would suspect that you could get full propagation across the column. Very uniform weak layer " at least where I was "