I went to a speech by savage earlier this fall. The point that I took away from it is that what captchas do is filter out the bad guys who haven't figured out a business model.

On the klingon point: They theorized that the particular organization was a bunch of PHDs rather than farmed labor - and that it had learned from previous 'example answers' they had submitted. That particular organization, it was noted, was also an order of magnitude more expensive than the others.