Quite a few brain (and cpu) cycles have been spent on 'author identification' software that allows to tie together pieces of text at various points in time to a single author.
I have played with gender-identification software[1], which has such a limit. Frankly, the identification seems to be more topically sensitive than it is gender sensitive. For example, if I put in my writing about robots it will id me as male, but if I put in my writing about cooking it will id me as female.
Combining the 'author identification' software with known identities (such as we have here on HN) will certainly make them more accurate. Hence, my desire for a system that limits such computations.