Thanks for replies. Abject failure on our first attempt. Turns out moving quickly up and down that rock is harder than we imagined. Especially coming off Middle Sister towards South. Took way longer than we thought to get down. Limped into Camp Lake and laughed at the thought of climbing South. 8 miles back to Pole Creek was easier. Will try again next year. Either in July when there's more snow or September when its a little cooler. Fun, but brutal day in the mountains.