Phil,
Personally I look forward to your take on Flashlight defense. I will look into your book.
A flashlight is a tool, and can be used in multiple ways to deter an assault (checking ahead for baddies, not looking like a victim type, etc) to improving your odds if an assault occurs (a moment of advantage gained with a flash to the eyes, a more powerful punch with the flashlight in the fist, or as a striking device, etc...). I'll take any advantage I can get. If the flashlight helps, I'll use it. If a handful of sand to the face provides the edge, then so be it.
There are many other tools that improve ones odds of assault prevention or self defense: Awareness of your surroundings, don't look like a victim, staying out of bad situations and locations, pepper spray, batons/maglites, knives, firearms, etc. All fill a niche. Many work together in a continuum of force allowing for escalation to any/all that improve your chances. Take a look at a police officers belt these days. Nuff said.
If I am able to carry more powerful defense tools and the flashlight gives me that brief moment to bring them to bear, then it is of great value.
The unfortunate reality of today's world is, many simple/practical methods of self defense have been removed as options to the citizens. Pepper spray, knives, and firearms are simply not options for most/many folks. Walking out to my car carrying my knife or gun in my hand in a ready position will get me a ride in a police car, a strip search, some cool striped jammies, and a cell mate named Bubba.
An appropriate flashlight can be carried in your hand without a second look. I can quickly survey my car before entering or light up the shadows if something looks suspicious. It is legal in schools, airports, and all manner of public places that limit all other self defense/prevention tools.
If the worst happens, I would much rather have a small tube of metal in my fist, than an empty fist. If a flashlight provides an advantage to those that have been denied other methods of defense, then I am all for it.
The flashlight isn't a super weapon, or the solution to all bad guy problems. But, to pretend they are useless or can play no roll in self defense/deterrence is in my opinion ignorant. Also, any tool in the hands of a fool can be useless or dangerous. That said, I don't want my information or options limited because of the lowest common denominators in our society.
TR