The nutritional value of protiens (including eggs) that you see in books and on labels is before cooking. Cooking reduces the amount of fat and moisture in meats only. It does not change the amount of protein in the meat. Weighing your meat after cooking will mean that you are eating more protein than you originally intended as the meat weighs less after cooking. The amount that you are getting is minor...but if you are dieting...
You wouldnt weigh your eggs after cooking would you?