Just to add for clarification: Do not hold the hot potato directly in contact with the rooster's leg. Stop the potato half an inch short of the leg so you don't burn it.
I don't have a rooster or any spurs to remove from one, but geez...that's the craziest thing I've ever seen. Both the judge in that one video just popping them right off and then the thought of using a baked potato to just remove them. Nuts! I'm amazed by the stuff I read on BYC sometimes. Wow.
I have to agree...it has to make you wonder...who on EARTH was the first person to think hey! I think I will stick a pair of hot potatos on my rooster's feet!
I use the Dremel tool with the disc for cutting metal. Just wrap the rooster and take off the sharp point of his spurs and claws. I don't take the whole thing off, just the sharp points. I think the claws do as much or more damage than the spurs.