Kenji Tierney is a wonderfully engaging speaker. Starting with memories of being introduced by his grandmother to sumo by way of watching TV with her he gives a wonderfully learned and fascinating talk on sumo and its development. The story of how the Japanese tried to impress Commodore Perry with a sumo wrestling exhibition and he responded by putting on a minstrel show is just one of many fascinating stories. If sumo has always left you a bit baffled this is a thoroughly entertaining 'deep dive'.