There are quite a number of rare (from a pro perspective) but interesting side patterns, based on the same plan: set up an ideal press or cover play in one corner, in relation with an enclosure positioned to take advantage.
For example, here all Black's stones, and and the stones. are working together on a large scale. Presumably first explored by Katayama Chiteki.
Although there are indeed not so many examples in pro games to study, there are some. These form interesting material from the point of view of framework theory. For instance, they often include use of a wedge on the side, and tenuki joseki.
Since in the diagram fits in with many amateurs' ideas on the use of influence, these are instructive patterns to study. Of course one should also look at the whole board. Often Black in playing this way is applying an ippoji strategy: omoyo play may cause panic in some opponents, but that doesn't mean it's sound. Therefore a technical discussion of how to play these sides is called-for. If White has some basic ideas on strategy here, it will be a great help.
Here White's basic ideas are at a or at b. The former allows Black to start the taisha joseki: this is a signature pattern of Ishida Yoshio. If White b, Black a for a complex of joseki that give Black a large corner: but the game will stay relatively simple. (The wedge White at c was played by Segoe in an old game.)
The options are the previous main choices with expected outcomes as before: plus White at c, in the corner. This was played in a game 2002-10-28 between Kubo Katsuaki and Yuki Satoshi (B); Black played the cover at b and an early struggle for a good ladder ensued, in relation to the lower right corner.
White can of course avoid immediate difficulties by agreeing to a ryojimari game.
This is from an Ishida magazine article. If Black is happy playing a 3564 enclosure the same type of formation can be set up from the (unorthodox) starting position.
This was played (colours reversed) in a game 1982-06-29 Shao Zhenzhong-Kanda Ei (B). The stone had been played to limit influence in the lower right. Therefore isn't so surprising, to slow the game down.
From a WAGC qualifier January 1982 Yang Jinhua-Cheng Xiaoliu: wedged immediately. The correct wedge point is apparently 10-3 if played at once, 11-3 if White starts in the left-hand corner and plays tenuki.
This formation has been used by Yamashita Keigo: leading to and . After White invades (at a or b) Black allowed White to connect to , building a wall on the left side.
There is an older example at perverse wedges
What follows was previously on the jabberwocks page.
This was played by Go Seigen against Kitani Minoru in a three-game match sponsored by the Jiji Shinpo. Waltheri doesn't have the date, but from the ranks of the players I've deduced that this game was played in 1933 or 1934. Kitani won by a convincing margin of seven points.
This combination appears only a couple of times in Waltheri.
This formation appears in 14 reliable games in Waltheri. Its most notable outings:
- Shinohara Masami played it against Go Seigen at some point in 1934-36
- Maeda Nobuaki played it against Go Seigen in 1935
- Takagawa Kaku played it against Fujisawa Kuranosuke in 1937
- Hashimoto Utaro played it against Cho Chikun in 1977
This side setup appears in 11 games. In five of them, it's played by Yamashita Keigo. Its most notable outings:
Perhaps I should say that the idea of the 4-6 example is something I found in a book of Shirae Haruhiko.