Honestly, Tesa, if you do read through the entire thread, you may find that your feelings have been replaced by facts.

Overall, I have found that the strongest feelings, regarding helmet use, almost always belong to folks who haven't looked into it in any detail. They "feel strongly" about it because they assume that bicycle helmets have tremendous ability to protect cyclists and so wonder how anybody could be foolish enough to ride without one.

When those folks learn about the actual efficacy of helmets (along with the actual risks of cycling, which are quite a bit lower than many cyclists assume) their feelings about helmets tend to become much more ambivalent.

Bottom line: wear one if you like. Nobody's suggesting you shouldn't. The only argument is that you should understand the realities of bicycle helmets: they're unlikely to prevent serious injury or death, and you shouldn't behave (on the bike) as though they can.