while I'm sure Ken would love to rake in beaucoup bucks from his book(s), one has to also consider that maybe he also wants to document things for the "historical record" as it were. Like other people in the band or whomever may go on to write their own books which will reflect their own perspectives and biases, or... maybe none of the band will and it'll all be lost once everyone involved is gone, so he wants to put his version of the story out there. I also think based on stuff he's said in various interviews etc that he kinda feels a bit slighted by Lindsey, that he (and maybe to some extent Richard also) don't get their fair dues in regards to what they contributed to these FM albums-- what ideas they contributed etc and all credit tends to go automatically to LB (e.g., Richard saying the band didn't really see the potential of Dreams but he did and pushed in his way to get them to give it a go; and Ken saying it was his idea to do the pre-chorus on Dreams (stillness....lonely....heartbeat....etc). People want their contributions recognized
So maybe his goal in getting a book out goes beyond just the NYT best seller list or lots of royalties.
