Should the science-savvy respond to Creationist objections to evolution theory with ridicule or understanding?

Obviously, we have to point out all the falsehoods, faulty logic, quote-mining, straw-men and outright lies, but what tone should we take when doing it? Most creationists don't properly understand the theory of evolution because they have been fed false information by, for example, their religious leaders, internet sources or even in some cases their high school science teachers. Furthermore, most creationists are unwilling to accept evolution because they feel it undermines their religious beliefs - beliefs which they feel are fundamental to their values and character. Should those of us who are better informed about the science therefore take a more understanding approach to explaining where these people have gone wrong? We are, after all, unlikely to change anyone's mind by calling him an idiot. On the other hand, it's my experience that in almost all cases no amount of evidence or logical argument will convince a creationist that he/she is wrong. Should we therefore take the more hing approach in order that any neutral, undecided parties privy to the discourse are under no illusions as to just how ridiculous creationist arguments are? My thinking is that the "reasoned debate" approach may give the false impression that creationist claims actually have some merit and are worth debating.