Look fellas, you can Google this shit all day long and come up with defences as long as your arm. They're not going to put every stated case on the internet for every amateur wannabe lawyer smart arse trying to get off a menial offence that they have committed either on the road, or in a criminal circle, there's liability written all over that. The driver in the blog thought he knew better, challenged the police at the roadside, caused a problem, and lost in a court of law.
CPS have a strange way of dealing with offences, and the result in a court is generally a little different to what went in. Deals are struck, and more than one offence will generally fit the bill. Unless you work in these circles, you would not believe how twisted it can become.
At the end of the day, if you want to flash people to warn them of speed camera vans, crack on, were all adults and can take the consequences of our actions. Just don't be surprised if you get caught, a cop will state "perverting the course of justice". Challenge him at your peril, I'll guarantee if you push too far you'll feel what its like to wear handcuffs!
And that my friends is why this country is in such a shit state! Too many people that THINK they know better, too much crap info on the internet misleading people into believing they know better, and too many lefty's beating the drum out of beat.
Soap box now firmly put away, now has anyone seen a good pair of tits recently?