I’m getting a lot of attempts to post comment spam, and they’re all failing because none of the spam robots knows the magic word.

The only reason my (very rudimentary) spam-deflection scheme is successful is because I’m the only person who’s using it, and it’s not worth the spammers’ time to work around one site’s peculiarities.

This suggests that a proliferation of very rudimentary local spam-deflection measures might work as well as (or better than) a single very sophisticated widespread approach.