Agreed that the cyclist did not handle this that well as it escalated, but I feel that his initial actions of knocking on the window were not out of a desire to create a big fuss and a video for youtube; both parties could have handled their discourse better, and the police officers having received training should have behaved better.
Granted the cyclists behaviour towards the end overshadows the reasonably calm manner in which he challenged the police for being in the bus lane, and makes him come across as confrontational. This impinges on what is essentially an incredibly important function of society, that we should be able to challenge and hold to account the governing executive (the police). Resulting in most of the replies on the last five pages being critical of challenging the police. Such unquestioning obedience of an institution with a poor track record of misuse of power is worrying, and is perhaps symbolic of the little attention and absence of any convictions for over 350 deaths in custody just since 1998.
I find the notion of an "attitude test" ridiculous. For a start the police officers in the video would have surely failed any such test, and the police should not be there uphold or judge such subjective measures as attitude. The imposition that one is able to judge someone's attitude carries connotations of moral superiority. The police officer's decision to ask for his details was clearly motivated by moral judgements, and perhaps a level of arrogance at having his authority challenged, rather than a belief that the cyclist had broken the law. This is demonstrated by the officer not stating which act they are stopping the cyclist under and for what reasons, and their need to exaggerate the force by which the cyclist tapped on their window.
If we are to continuing functioning as a society that perceives a need for a police force, then we should be able to challenge them on all of their actions and not expect them to act in an aggressively defensive manner!