(also during the actual game with more details, but I can not find the exact time again). Edit : can not find game3 commentary but during game 4 he is coming back to it again with interesting details as for why this is a great opportunity to inspire human players : https://youtu.be/yCALyQRN3hw?t=7097

Basically, once in ancient Japan and more recently a Chinese origin player in Japan, both incredibly strong players, surprised everyone with never before seen moves that subsequently where integrated in modern game theory. The hope is that the same could happen here.