Chicken Sexing: An Unsung Art

As I read today's lively exchanges on The Dabbler on the subject of chickens, my mind naturally turned to that vital yet strangely unsung art - chicken sexing. Vital, that is, to poultry production and, especially, egg production. For hatchling chicks adjudged by the skilled chicken sexer to be male and therefore not required for egg production, the outlook is grim indeed (and very short). This is a fact worth mentioning to egg-eating vegetarians who imagine that their dietary choice is saving vast numbers of animals from needless death (as is the sad fate of male calves in a system geared to producing vast quantities of the cows' milk enjoyed by lactovegetarians). The Wikipedia entry on Chicken Sexing is not for the faint-hearted. The paragraph on Vent Sexing is especially harrowing... ('Many professional vent sexers are Japanese...' I wonder how they get on at drinks parties: 'So what's your line of business, Tojo?')
If anyone can shed further light on the place of the 'example of the chicken sexers' in the internalism/externalism debate in epistemology [see Trivia], I'd be delighted to hear from them.