📝H. G. Muller wrote on Sat, Apr 25, 2015 10:03 PM UTC:
Well, I have given the reference to the hard evidence: the Middle Shogi Manual compiled by George Hodges in collaboration with the research group at Kyoto. It contains the references to the historic sources on which it bases its conclusions, which I have paraphrased here. The sources themselves are of course all in (archaic) Japanese, which I cannot read at all. But I have no reason to doubt Japanese academic research on this.
In fact I have a lot more confidence in Japanese academic research than in some western clown that 'just knows things' without being able to tell where this knowledge comes from, and then blames others for his ignorance. But everyone can of course decide for himselve whether he rather believes a Japanese history professor or a bragging westerner, on matters of japanese history.
And the 9x9 game of course became only popular after the introduction of drops. That transformed it from the boring Shatranj-like game to the fast and exciting game Shogi is today.