The 20/70 corrected to 2020 rings a bell. However, I did see a list of airplanes the other day which aircrew are allowed to have eye surgery and still fly. It had to do with the pressurization aspects. I.E. the b-52 guys could not have surgery but the B-1 guys could. The buff has a combat setting for the pressurization and I guess the Bone does not. Also, even an eye surgeon can't tell when lasik has been done...father is an eye surgeon.