I was an adult when I started playing tennis seriously, but try as I might to ratchet up my game I seemed to have plateaued at intermediate level 3. I was too good to enjoy playing with beginners, and not good enough to play with advanced players who certainly didn’t want to play with me. So my tennis life was not a happy one. Then I discovered pickleball, the relatively new racket sport that’s all the rage. Once I started playing I found I was much better at it than tennis...