1. Tani is rapidly moving up the ranks. He's only 10. Presumably the rating difference was much larger just a few months ago. 2. 300 points is still quite a la

1. Tani is rapidly moving up the ranks. He's only 10. Presumably the rating difference was much larger just a few months ago. 2. 300 points is still quite a large rating difference. 3. In many disciplines the best practitioners are often not the best coaches. You might speculate that being the very best and most talented would make a worse coach since the struggle to increasing levels was easier. 4. Even Tiger Woods had a coach at his peak.