This discussion has put me in mind of a rather dubious paper from Arxiv earlier this year,
here. In it the author, Serge Galam, suggests that if one wants to win over public opinion on an issue the best strategy is to overstate ones case, beyond where the evidence will take it.
I don't actually agree with his opinion that evolutionary biologists overstate the evidence for evolution but that is beside the point.
Perhaps dickishness is a similar strategy, it won't win over the 'inflexibles' on the opposing side, but if you stick to moderate reasoned debate you will lose out to the dicks on the other side when it comes to convincing the floating opinions.
TTFN,
WK