It is the Ichiken group (i.e. the Ichiriki Kenkyukai), brainchild of Ichiriki Ryo, the new Kisei (also current Honinbo challenger and now Gosei challenger). He thought of it some time ago, but the move of Nakamura Sumire to Tokyo provided the final impetus.
It is unusual in several ways. First it has what might be the current top two players, male and female, namely Ichiriki and Women's Honinbo Fujisawa Rina, plus the top two future prospects, male and female, namely Fukuoka Kotaro and Nakamura Sumire. And that's it! Just four players.
Normally, study groups in Japan are open to a wide variety of players, but the rationale here is a complex one. At the practical level, these are busy players and getting them together at the same time is problematical. They will meet once a month and play each other in fast games, 30 seconds a move. In other words, they can manage only three games in a day and so that makes four players the limit in their setup. As to why the same four players, that's partly because Ichiriki's desire is to get Japan back near the peaks of international go. Rina and Kotaro are the best prospects, but interestingly, he thinks it's a long haul - 5 to 10 years.
The strategy is clearly to create a hothouse atmosphere in which they can grow Brandywine tomatoes rather than supermarket Globe tomatoes. But the fruit being nurtured on the vine is not just Rina and Kotaro. Asked why she would want to help a rival - Sumire - to improve, Rina said she didn't see it that way; she saw it as a chance to improve herself (and she also noted that so far she's had a hard time against Kotaro). Ichiriki made a similar comment: the group would stimulate himself. This is somewhat reminiscent of Magnus Carlsen's comment that he is no longer interested in playing world chess championship matches unless his next opponent can be the new talent Alireza Firouzja.
What we have yet to hear, of course, is what the sub-elite players think about it all
