Hello holm0299, I can't find the exact post(s) that talked about removing the washer (some of them called it an o-ring) right now. I'm about to head out but I can search more for you when I get back if needed. I'm pretty sure it was somewhere in the last 4-5 pages of the "part 2" thread about this light.
You could always try it yourself real quick since it's really easy to take on and off. All you have to do is unscrew the part of the bezel that holds the optic in in order to show the LED. Then you just pull the little washer off (mine is clear plastic with some stickiness on the underside to hold it to the LED). Just pull it off and screw the bezel back on. If you don't like what happens to the beam, just put the little washer back on. Anywho, I'll check back later.
P.S. The link to "part 2" is in the first post of this thread.
Edited to add:
https://www.candlepowerforums.com/threads/182082&page=10 - post #286 and down a few. Post #288 said his hotspot is smaller and it throws better with the o-ring in but mine is the exact opposite. I know I read about that in a few other places too but there's no need reading all of them.
Also, from reading you'll find that you can bend the positive spring (in the head of the light) to allow AAs to work in it (with C adapters that is). You just have to bend part of the spring so that the big gaping hole in the middle of the spring is gone or has part of the spring going through the middle of it.