Why didn't any of the consultants I've seen for my permanent pain(*) mention anything of the sort?
Because they're consultants, that's why they get paid. Assuming you are a woman, hard to tell on the 'net, they still have limits as well - ask any woman who's had a long birth.
You don't even realise that manflu is a sexist stereotype - you're using a sexist stereotype as proof of a sexist stereotype and you don't realise why that is not rational thought.
Because it isn't. There's scientific proof that estrogen fights the rhinovirus, mostly because women create the child's immuno-supressancy. There's also hard proof that men's bodies are built to withstand pain better (Musclature - Thyroid growth). And that while men only have 2 main hormones that keep steady states, women have several that are fluxing constantly.
a stereotype, but like a lot of stereotypes, it's just an exaggeration of the truth. The Rhinovirus is beaten by the immune system pushing it out, which is experienced by most women once a month; but almost never by a guy (apart from illness). That's why it seems to have a marked effect on men because they're simply not used to it happening to them.
Women, environmentally, rarely grow up with brawling, so they're less used to dealing with sharp stabbing pains that come from pecking order fights. They are more likely, however, to self-diagnose problems, and thus gain more from placebos.
The real problem with pain medicine, which has only recently been revealed is that men and women feel pain differently, due to them having different sized brain sub-sections- even with the same size heads: they develop differently. Most of the research into pain medicine was done in the '70s with MALE rats though, and scientists are now thinking that the stated tolerances ARE sexist, because no-one thought to calibrate for females - as they assumed the reaction was the same.
It's actually quite a new field of study. http://news.sciencemag.org/sciencenow/2008/12/23-02.html
I can only give you evidence for what I've experienced, of course. And there are obviously variations to the rules, but Morphine works far better for guys - and that's proven, despite being a sexist stereotype.