Was climbing an iced up hill with my fat bike yesterday. The path is asphalt but being in a ravine the ice and snow could not melt in the sun so it was a literal ice rink.
Although both my tires are studded, I kept hearing my rear wheel slide as I was pedalling. I didn't have any problems with them anywhere else I was riding through ice. I guess uphills are still a challenge but at least I was still moving up.