Re: Ratings are approximate
It would be interesting to see if players from different regions averaged more or less ratings points at a big event like Worlds than their average ratings going in to see if there are regional differences. There's nothing in the process that inherently would have a regionalization effect except perhaps some international issues that got squared away once the Scandanavians and Japanese played a few more events against the U.S. players.
Let's say there's actually some pocket that is 10 points less than they "should" be. Since they are playing each other, their performance is relative to each other for most events so it becomes irrelevant in terms of whether a player thinks some players are too highly rated to play against. In other words, even if all of their ratings were boosted 10 points, it migh not change the behavior of the players in terms of their division choice from what it is now.
If top rated players in regional pockets aren't getting better ratings than they expect, even if winning, it's more likely that there's a subtle influence causing them to not plays as hard against the course versus just enough to beat the other players. That's only smart golf to play to win even though your rating might not do as well.
Another influence might have to do with how tough the courses are in an area. There's no question that each throw is worth more on short courses and lower rated players can play closer in score to the better players to flatten the round rating output. Tiger would much rather be playing tougher rather than easier courses because it's easier for his special skills to separate him from the crowd. Same thing happens in DG. Feldberg told me that he feels the difference between his rating and Climo's is that Climo rarely plays C-tiers and only a handful of B-tiers compared with Dave.