Yeah, boy, how rude and nerdy of people to ask you to back up a claim you make as evidence to support your position.Here we go again...Nerdy fans, like you, expecting someone, like me, to come up with detailed answers to something I read years ago.
Your exact line was: "Since SHATNER's books outsell ALL THE OTHER books?" And you know this because you recall reading it somewhere years ago, probably on the Internet, that most reliable of sources. Can you see why some might be skeptical?
I'm not picking on you, I'm just doing my bit to point out that wild claims like this backed up by insubstantial evidence is exactly why the Internet is such an unreliable source....