I just watched some youtube clips of the 1977 Wimby' match between McEnroe and Conners, a match I'd never before seen. I noticed that in the year 1977, McEnroe had not yet developed his recognizable signature service motion. It was surprising to see him serve more conventionally.....never seen that before. Does anyone have the story on this.......i don't think I've ever seen it discussed or mentioned anywhere in bios' etc. I'm assuming that he developed it at Stanford?