Whakakihia te rerenga e whai ake nei: Ko te whakaaro o te patunga o te pawn ki...b5 me...a6 he tawhito rawa. I whakamahia e Karel Opočenský te whakaaro ki etahi atu, ko Gideon Ståhlberg i Poděbrady 1936, ko Paul Keres i Pärnu 1937, ko Erich Eliskases i Prague 1937, ko Theo van Scheltinga i te
Ko te Buenos Aires Chess Olympiad 1939. I muri mai, ko te kēmu a Mark Taimanov ki a David Bronstein i te Tohu Whakataetae, Zürich 1953, i aro atu. Ko te nuinga o enei kēmu i timata hei King's Indian, me te Black anake i muri mai ka takaro... c5 me... b5. Tērā pea ko te kēmu tuatahi e whakamahi ana i te paerewa 1.d4 Nf6 2.c4 c5 3.d5 b5 ko Thorvaldsson <unk> Vaitonis, Munich Olympiad 1936.