Adam I know you said you won't be replying to this thread again so I'll fire away ;)
I am surprised you cannot see why your attitude provokes the responces it has. You are basically saying that you are an above average driver (how do you know this or is this your own assumption and what would you class as an average driver?) and because you are a car nut ( "I know cars" etc) this means you are somehow more qualified to comment on what constitutes speeding etc.
As has been pointed out, the laws are there for a reason and are not for you to decide what suits you and when. Yes we all have been over the speed limit at times but I don't see how that makes anyone a hypocrite, it is not always easy to maintain the exact speed of a speed limit for various reasons. What I think people are getting at is that ( to me anyway ) you are coming across as someone who is almost proud to speed even excessively and without any doubt, this is dangerous.
Excessive speeding constitutes bad driving IMO. Just because you are intelligent doesn't mean you can see into the future and see a potential accident waiting to happen around the corner which just might have been avoided if you had been going just 10 mph less....