"Perhaps I am wrong but I refuse to just quietly put up with my lot and accept being treated like worthless s**t because I ride a bike and do not have a car"
I've never suggested that's what people should do - hence the PoP demo; and suggesting that people contact people about the piece of awful infrastructure in the OP. In fact that's the very opposite of 'quietly putting up with my lot'.
As for it being okay to break the law 'depending on the circumstances' - this is where the problem lies. Which circumstances? Who determines? To Gembo and others the OP section circumstances 'force' or 'justify' breaking the law. To the police it clearly didn't. To a driver in a 20mph zone being tailgated 'forces' or 'justifies' breaking the law. To me and you it doesn't.
Who is right? The only way to be certain is to actually adhere to the law; and actually speak out against those things that would force us to break the law if so inclined.
Also "You mention driving on the pavement. I frequently see drivers driving on the pavement so that they can get round another driver who is turning right. Is that justified?" Again, I never said it was, I was using it as a query, which you've answered interestingly. You've admitted that, similarly, in certain circumstances breaking the law in such a way in a car could be justified. That's exactly what the drivers who do it think - the reasoning may be skewed (justified because they need to stop at that house and there's a car already parked on the other side of the road so if they don't park on the pavement then they'll block the road, for example). Now you and I know that you just park slightly further away and walk, but in that driver's mind he's justified.
So how do you counter that? You tell him he's not justified, in the same way Baldy and I don't think Gembo was justified to ignore the road sign. Who determines who is right?
Personal opinion surely can't be the determining factor in deciding whether a law should be stuck to or not?