re: Let’s Talk Planes

Also, since this seemed like a good opportunity for me to understand it better, and I’m genuinely curious about it, I did a quick search and found this. In general I agree with the conventional theory you mentioned, but this was an interesting read. It’s written in Japanese, but you can translate it with your browser:
http://kurayuki.abeshoten.jp/blog/14437/

Sorry if no one here is interested, but I thought it was an interesting read.