I don't file mine either. As I first started developing them, they were thick and hard crusts on the tips of my fingers. I had difficulty using a computer keyboard because they were so thick and without feeling. The more I played, they eventually peeled themselves off. The callouses that I have now resemble nothing like what I started with. My callouses now are practically invisible. They're not still and hard and numb like they started out. They're flexible and I really don't even notice them. They don't stand out or even look like callouses anymore. I can play for probably 2 to 3 hours straight and not even notice pain. I guess my opinion would be to leave them alone and eventually they'll smooth themselves out. At least they did for me.
