I did not use any steel wool in my bikes, or JB Weld. I'm not sure, but I think they are trying to help the sealer bridge the holes. I just used masking tape across the holes, and it worked fine. There is a small hole that is blind behind the seat post, where steel wool might help, but I just put a little more sealer in that area. Hopefully guys that used steel wool will describe the benefits of it.