In reply to various:
Lots and lots of interesting points here. Also, a much more complex issue than I'd originally have thought.
The way I would read it is that whilst participation in the sport is gender neutral - or at least not a vast skew towards men (anyone with a climbing wall fancy running a query against their database on Gender?), there are a lot less competitive female climbers (of all ages) than male climbers. This probably has a knock on effect to number of female route setters and testers.
However what has come out is that the female climbers are not, in any way, "worse" in standard than the men, and whilst the evidence is anecdotal, there is evidence that female climbers can most certainly compete directly with male - whether it be anecdotal stories of the female winner flashing the male final route after the competition, or a more scientific approach of actually looking at scores on a competition route climbed by both (AlisterM's post above).
This surprised me, in that I suspected that the route setting would be for power and strength which would mean that female climbers would be at a disadvantage - apparently not!
What has also come out is a lot of information on the psychology of youth climbers. Some views are that gender groups perform better when segregated, that girls prefer to climb in competition with girls. This appears a lot murkier issue to me. First of all, it's a blanket statement - does this apply to *all* girls? And should the girls who want to have the fun of embarrassing the boys be banned from doing so?
I guess to me it comes down to my world view that in 2013 people should be treated the same regardless of gender unless there is an overwhelming reason to do differently. For my own view, I'm not convinced that in this case the overwhelming reason exists.
In pretty much every other area of life (politics/business/etc) not only do males and female compete on the same playing field, but it is actually illegal to segregate that playing field. Sport is a bit of an exception, where women's sport is, frankly, poorly regarded, covered and funded and women are sidelined in most sports. There's only a few where the female competition (if it exists) has anywhere near the same billing, prize money, etc as the male. This again kind of offends my sense of equality.
Climbing, as a sport, feels to me as one where the is an opportunity to head for equality and *not* to follow the crowd or history (where women's sport generally didn't exist because women were confined to the kitchen) by dividing competition on gender lines simply because we always have done so.
Given that it's child's play to use the same routes for both girls and boys (in fact, as explained above, it already occurs to an extent) although a prize for top boy and top girl could still be given, of course, to satisfy those who feel that segregation is the way forward, I think there's an opportunity to try open competition and see what occurs.
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Just a final point. There's a couple of kids at my local wall. Very, very good climbers. They belay each other up routes (generally the seriously hard stuff) and generally have a good time and appear to have a great friendship. One's a girl, one's a boy. It appears strange to me that when it comes to an official competition, they will not be allowed to do what they do every week down the wall, which is compete with each other.