Someone remembered Nats players working in the offseason in schools as substitute teachers to make a few extra $ (SAC) and that Darold was one of them, in a PG County School.
I don't remember anything about him working as a teacher but I do remember that he was in the National Guard (or equivalent, avoiding the Viet Nam war, like the rest of us) and missed a big part of the beginning of the 1969 season. So it was with great anticipation that he returned, late May, and on his first encounter with new manager, Ted Williams, Williams first question to Knowles was "does a curve ball really curve" and Knowles answer was "they told me that you would ask dumb questions like that". True story (I remember reading it in the Post the next day).