I prefer to go with a more engineering method, go find the 85th percentile. It's what used for speed studies on vehicles, might as well use it for the driver
Shockingly I don't lie about my distance because when people see me hit the ball they go, "Oh yea, he can hit it that far". So I rather just be honest then undervalue my skills.
I would say higher handicappers OVER estimate their distance by a lot more than lower handicappers.
Joking aside, @flopster put it pretty bluntly that as long as you know how far you hit it doesn't matter how far you say you hit.
No one here doubts your distances. If someone else puts a bogus number down for their own distances, that does not take away from your statements.
I never noticed the association people place on distances relative to handicaps nor how much judgement is placed on a handicap until I got on here. I've never even had an official handicap, I just put down 4 cause last year it seemed like my avg. score was +4 for 18. I'm sure if it was a real handicap it would probably be higher because I don't consider the courses I frequent to be very difficult.
As far as club distances go vs handicap, I don't pay much attention. I get beat by guys all the time who don't hit it as far as I do. If a 20hcp'r says he hits it 300yds when he catches it I believe it, but I don't think he can repeat it very often or keep it straight. Oh well, I'm off to test a couple 48" shafts :)
There is a measured correlation between handicap and club head speed. That's why handicap is a good check.