The only time I worked an Open was the US Open at Merion in 1981. I was on the second tee all week and doing something like that the good news is you basically get to see everyone in the entire tournament in one spot for a brief time but in a very close observable way. There sure were a few memorable moments.
One of the more interesting items, though, was walking along with Watson from #2 tee to the finish (I guess I was an observer) who must have been in the last group that Friday. It struck me how much he never tried to do anything fancy or risky. And it also struck me how little he talked even with his caddie (almost nothing). He would just walk rapidly up to his ball, stand there next to his caddie for about five seconds, take out a club, hit it pretty quick and march on again to do it the same way every time. Watson must have been basically a "feel" player as he never seemed to ask for or get much info before hitting a shot.