Wasn't that the reason Abbott left Zakrasjek/Colorado Springs? He wanted individual attention, not to be one of many (one has to wonder, too, if he looked at Farris and Aaron and went, "Oh, crap."). But then some skaters work better in a group environment or an environment where they interact with rivals on a regular basis. Kori Ade often teaches three or four of her male students at the same time, even Brown in groups with the others. And if you look at the current CS situation, you've got Aaron, Farris, Armin as the top dogs (with Brown arriving soon), and then a whole crop of Senior/Junior men that Krall also teaches, Kaugars, Dolensky (at least I know he was at CS at one time, is he still there?) and so on. And it seems to work very well, like they bounce off each other.
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I was just thinking, too, about the situation with Alexei Mishin. He had Yagudin and Plushenko training together and that obviously didn't work. Now, he tends to keep Gachinski and Plushenko away from each other, though they do sometimes train together, it's rare. I think he will still put Tuktamysheva on a session with either of them, but not his two men together. This helps to remove some of the tension factors that crept in with Yagudin and Plushenko. I wonder if it's partly a culture thing?