Yes, it goes through the snow band below the summit pinnacles. Saw your message board post, this wouldn't give you an accurate depiction of what you will see in late August. I did it when snow and ice covered so don't have any rock info for you but I do know it is very loose, not sure you can really protect it. When I did Middle Sister, I ran into a guy and his dog who had just done North Sister. It should be loose ledges and no real climbing but I can't guarantee that. Good luck.