Hello TPC, as far as I am concerned gum trag is bad stuff. Dye will not penetrate the leather any place gum trag has been applied. I always sand my edges first. After they are smooth I apply water to the edge and rub with glycerin soap and then burnish with a burnishing tool. Or with canvas if you don't have a burnishing tool. This will give you a very smooth edge. after burnishing I dye the edges and apply a sealer such as Wyo-sheen to the edge to seal it. I don't like to use Edge Kote because in some instances it has a tendency to crack. Bob Parks has a short tutorial on finishing edges which is really great. Look it up on line, I think you will enjoy it.