EDMOND, Okla. — Hard to believe we just keep doing this story over and over again. It’s true, once again, mortgage rates are at an all time, historic low. Homeowers everywhere are calling the bank to check their rate. Many banks around Oklahoma are offering 3.375 percent on a fixed-rate 30-year mortgage and 2.75 percent on a 15-year mortgage. “Yes. We’re very, very busy....