bollocks, says I
I'm going to add my name to list of here-here's (or hear-hear's - never know which :confused
and add the opinion that labelling something as 'evil', or as a 'sin' is just the kind of thing that winds me up about Catholic doctrine in the first place: with a recent example being the Vatican statement about the Schiavo case.
It sounds simplistic, is deeply judgemental, and (as you so rightly point out) doesn't help understanding and debate of the issues.