Female Performance On Fieldwork

I read this article on the F-Word blog: "Women, confidence and fear of male judgment", and thought about my own performance in certain activities in front of men. The obvious one for me was fieldwork, so I commented:

I'm a palaeontologist, which involves a lot of fieldwork. I assisted on an undergraduate fieldtrip, driving one of the minivans. Although there were three female drivers I was the only one who didn't opt out as soon as they could, so I found myself "competing" with male drivers. Despite being a competent driver (I have never had a problem with manoeuvres), with all the other drivers watching I managed to burn out the clutch, earning myself the nickname of "Clutch Lady" for the whole fortnight.

I'm also fairly nimble on my feet and pretty good at bouldering (although I don't pretend to be any good at actual climbing). A 6-ft scramble would have been very little trouble for me if I'd been on my own or in a group of girls. But faced with two men offering a hand to help me up I stumbled, lost my footing and had to be hauled up. I beat myself up about it for the rest of the day, because I knew I should have been able to make the climb.

I don't know if we're so caught up in worrying about what the men might think that we fail to concentrate on our activity, or whether we subconsciously act how the men are expecting us to act. I am expected to be a bad driver because I am a woman. I am expected to not be able to scramble up a rock face because I am a woman.

Not to take away comments from the F-Word, but I'd be interested to know what my readers think, male and female. Is it just having an audience that does it? Am I imagining my perceived competence with a female audience and incompetence with a male audience? Anyone want to share their fieldtrip shame?

Interestingly enough, I have never underperformed when giving presentations at SVP. I don't know whether it's that women are not expected to suck at public speaking, or whether it's only really physical performance (something easy to assess objectively), or whether it really is all in my imagination (and presumably the original article's writer...).