If a golfer is honest with their scores, the handicap is amazingly accurate. The scores pretty much follow a bell curve exactly. Here are my last 10 scores net to my handicap:
+0.7, -2.3, +1.3, +3.5, +2.3, +1.9, +0.5, -1.3, -0.4, +1.7
And, I think home course plays a big part in that too. My home course has a few configurations, but handicap and slope ranges from 68.8 / 125 to 71.4 / 137. My buddy's course is 71.0 / 137. His course is easily 3-4 strokes tougher than my 71.0 / 137 configuration.
Member-Guest at my club this weekend. I like that he's a 6 because it'll post, but he'd be a 2 or a 3 if he played my course more often. Format is interesting. All scoring is net Stableford.
Thursday - 18 holes: best ball
Friday - 27 holes total, 9 holes: scramble, 9 holes: shamble, 9 holes: alternate shot
Saturday - 18 holes: individual play
Flighted. Winners of flights face off in a 3-hole shootout.