PhilippD: What I dont understand now, is that my stroke average doesnt change, I dont get the algorithm, when I played a couple of rounds under par and keepstaying at 68.30. LasttimeI played a -4 on nine holes St. Andrews and it even wetn from 68.25 back to 68.30. Are you kidding??
I think you're forgetting the 37 (74) at Pinehurst, that's what will have made your average rise slightly. I see you've scored 32 (64) and 31 (62) at St Andrews since than and it's consequently down to 68.16.
Your average is right and anyway it really doesn't matter. Soon you will have played the 40 ranked rounds needed for saturation and your "average" will only go down.