Uummm... thanks for the visual. None of that advice worked for me. My problem was a crack in the callus that went down to the "regular" skin level. I had the best luck removing the callus (sanding or clipping) so the depth of the crack is zero, ie the bottom of the crack is flush with the regular skin level because the callus isn't there anymore. Then it healed quickly like a regular shallow cut (instead of taking forever trying to heal callus to callus across the crack).