I received a few comments about the ice mass on the Muir Snowfield. Avid Rainier skier Ron Jarvis had this to say,
"When I started playing on Rainier in 1991 there were no dismounts required while skiing from Muir to Pebble in late summer/fall and as I recall that seemed to be the case right up until the last 2 or 3 years (dementia notwithstanding :-) ).
I would also add that similar conditions (volume/snow-ice depth) also seem to be the case on the contiguous neighbor to the east, the Paradise Glacier."