Was walking with my Level 2 class this morning just above the Atwater plot, when we witnessed this slide being triggered by a party of two above us. It looked like it broke right at his feet as he crossed the short wind loaded lip and he possibly slid or was carried a very short distance. Was interesting to note other parties just continue on past - I have no idea what, if any conversation took place - and up the ridge. Also of note, there were at least a few parties higher on the ridge that had already crossed this slope. We went up and took a quick look at the crown and did a quick ECT (ECTP 4 SP), the wind slab failed on graupel from earlier in the week and included all of yesterdays snow and this mornings new wind transport. Avalanche was big enough to injure, but in this terrain wasn't high consequence.