From Debbie's Kitchen:
Whether you are trying to pan fry filets, rib eyes, NY Strips or chops of any variety it is important to know how to cook your steaks to retain all of the moistness and tenderness. The bane of all pan frying is the thick gray band of meat that is tough and chewy and depending on how much you overcook your steak determines how wide a band you end up with. You can't imagine how desperately I want to explain expanding and contracting proteins, retention of enzymes etc. but I will save that for another time. Suffice it to say that if you cut open your steak and find that treacherous gray band you can be certain that you are going to have to chew a little harder and you will certainly need to add a dollop or two of butter to replace some of the lost moisture.