6-4 point
Unconventional corner opening play developed by Sekiyama Riichi. This is played about 0.1% of the time. Recently it has been used by Yamashita Keigo.
Commonly White then approaches at a, or Black makes a shimari at b or c.
There are some recognisable 6-4 point joseki. They usually occur in practice as tenuki joseki.
is possible too, but invites the severe play
: this position has the reputation of being the toughest of the double kakari family. (See 4-4 point, double high approach.)
Calvin: A double 6-4 opening is sometimes used by Shirae Haruhiko. Recently, Yoda Norimoto used two 6-4s as white in a game against Cho Riyu. The fuseki starts like this: