re: How many here know about the symptothermal method as well as the creighton method?

They’re not taught because this method relies heavily on human judgment (thus it fails a lot based on human error). The perfect use rate is high, but typical use rates are bad because people screw it up. It’s a good way for a woman to know about her body & whether her cycles are normal, luteal phase is sufficient to sustain a pregnancy, etc., but it takes a lot of diligence if used to prevent pregnancy.