What I have done with success is to alternate with a coarse diamond bench stone, to define the high spot, then go to the bench grinder or better yet a die grinder and LIGHTLY grind the high spot only and return to the bench stone for a nice long session, then repeat as necessary. Never bear down when power grinding and never go near the edge and keep the blade cool by using the mass of the blade to absorb the heat, the edge and sides are low mass areas. If you feel the blade heating up a little, you have to stop grinding. If you feel the need to quench, then you have ground the blade too aggressively. By alternating you can speed up removal greatly but aggressive dry grinding will result in harm to the blade.