I don't do much winter season hiking so I have to ask. Is it ever safe to hike on a cornice? I would think one would want to walk as far from the edge as possible. How would one assess for safety?
This is a tragic event. No witnesses to say what really happened.
I personally believe, answer is to play very conservative. Even abandon proper summit and have a photo shoot / lunch before the summit. In poor visibility it is unlikely cornice could be accessed properly. Risk is multiplied.
In perfect sunny and clear weather, follow very conservative line to the top, if you really want to bag that summit in winter/spring season. If part of the group and someone carry rope, it is a good idea to rope up last segment. If no rope, to go to summit one by one etc.
If possible, during the climb up, look for the feature of the mountain and determine where edge could be. On Harvey that was not possible, but some of the group members hiked up to summit multiple times before. Solo, you are decision maker.
When you climb Wedge arete, walk up foot left of the edge in front off you, look up and access cornices you will see on the rim, if you plan to descent to Parkhurst Col.
On your way to Hanover, take a mental note of the cornices for your next weekend climb ob Brunswick.
I hiked/climbed a lot before (and bike mostly now), and I was always uncomfortable seeing people in summer having lunch on the edge of Chief, Eagle Ridge or Porcupine Rim in Moab. People are fascinated with having feet over the edge. Who knows, maybe some of them carry that comfort from summer to winter/spring conditions? Winter/Spring conditions are complicated. That is why we have a something called snow science.
Important is to keep going to the mountains, gain a lot of millage (experience) and speak up. Read, comment, ask, share and discuss ...
Be safe and see you in the mountains.