I live in the Rockies and hike and run and x-country ski. I live at 6500' altitude and I can tell you that x-country skiing at 10,000 feet is pretty rough even though I am acclimated.
I've had relatives from Ohio come here and they complaint about headaches, nosebleeds and swollen feet.
Suffice to say that this article is dead-on.
Make that back to the Rockies. The 10th division hut system is still here from their WWII days.
Regardless of the accuracy of this particular article, Anaconda definitely did highlight the need for an actual mountain division. Nothing better than practicing at altitude, in the cold.