I learned recently about someone who deliberately posts controversial blogs.
Used sparingly, this can be an effective way to stimulate debate and also raise your visibility.
… if it is used too often it can have a negative effect on your credibility.
An example of a similar situation is the boss of a certain airline here in the UK – making preposterous press releases about future plans just to incense people and kick off debates.
It worked a few times, and also generated a fair amount of press coverage, however it has been overused and in my own opinion has now really damaged their credibility.
Just like story of the boy who cried wolf, if you are blogging just to incense people you need to be aware of the effect on your credibility if you do it too often.