I don't know what the chances are of having "D" all the time after surgery. Have you asked your doctor? My daughter had surgery that seems similar to what you are thinking of having almost 4 years ago, and, if I remember correctly, her bowel activity returned to normal after a few weeks. But everyone is different and one person's experience may be different than another person's.
You said you are thinking of having the surgery. Why are you thinking of having it? What would your situation be if you have surgery and if you don't have surgery.