The study he did isn't broadly valid because he only tested using a captcha system that is quite abysmal, and for which the results were not surprising. If he

The study he did isn't broadly valid because he only tested using a captcha system that is quite abysmal, and for which the results were not surprising. If he wants to increase conversion rates, he should get rid of the irrelevant fields such as date of birth, zip code, country, gender, and check-to-agree to legal contract. Ha, checking the actual site, "sign up" leads to "pricing" and not a sign up page. So much for their grave concern about losing sign ups at each stage. On the other hand, his link to an article about including Honeypot fields is good advice and valuable. Timestamp analysis is not so great since it requires javascript and cookies. The more stuff you require the more users drop off. The problem with captchas is bad captchas that are impossible for humans to decode. Sometimes the reason these are used is because simpler captchas are implemented in a faulty manner that allows spammers to decode them without even having to do OCR. So the site developer upgrades to more complex captchas rather than fix the underlying problem that is breaking the captcha security.