Well, at least the author linked to WhitneyZone.
She picked the worst day in the last 20 years as her day to climb. Except for a day with a fatality, this was definitely the worst accident, considering the number of people sliding out of control. Fortunately all the people she saw have recovered (I am assuming that.)
The other issue is that the accident occurred pretty early in the morning -- before temperatures rose to make the snow less icy. People got up high too early, and found dangerous conditions for anyone without crampons.
My recent Shasta climb was a good example. I (unfortunately) took the ranger's advice, and left Helen Lake at 4 AM (too early). That put me on the summit by 9, starting down at 10. Temps, just like on Whitney that day in June, were so cold the snow was too icy to glissade comfortably. It was hell trying to use my ice axe to keep the descent under control. An hour later would have been better, 2 hours even more.
