Peter A Goldsbury
Shiai is competition in the sense of a tournament
I'm familiar with that term, but not kyoso, so thanks for the explanation. The shiai form of competition can diminish a martial art, IMO, as it removes the aspects that differentiate it from a sport.
However, I come from a culture where competitive sport has always been seen as character building (although some professional athletes may not demonstrate that <vbg>). And I would argue that team sports provide opportunities in that regard that are missing from the martial arts.
Competitiveness can get out of hand though, and Ueshiba wasn't the only MA master of his generation to have reservations about it. Towards the end of his life, Funakoshi (introduced karate to the rest of Japan from Okinawa) was concerned he had done the wrong thing in introducing competition into karate, too.
Personally, I don't really have an issue with competitive "martial arts", although I'm not interested in them myself. But I don't think they should really be called "martial arts" anymore (martial sports, maybe).