Dating can be like doing job interviews. You show off your strengths as often as possible.
The reason why most of his dates didn't go well was because there are so many factors in compatibility that he didn't account for. Personality is still distinct from most of the questions on the website. How you feel about things has very little to do with how often you speak of it or how much you want to talk about it with others--among other things.
In any case, I kinda feel like what he was doing was cheating. It's one thing to try to figure out what's important to other people--and it's another to completely ignore what's important to himself! While he answered the questions honestly, it annoys me that he only did questions that potentially compatible women were interested in. Doing stuff like that cuts his own personality out of the picture.
While there is a science to compatibility and to fishing out the people you want to spend time with out of a bunch of people, I think he took it too far. While his endeavor was ultimately successful, he also cut a lot of women out of his pool that he could have had a chance with but didn't include because they didn't fit his "list."
That's the problem with a lot of people who are interested in dating! They have a list of everything that their significant other must be and then overlook equally good people with qualities that they hadn't even thought of. If you're too busy making a checklist of what you want, you miss out on a lot of good opportunities. To me, his efforts sound wasteful--and maybe kind of desperate.
There's a reason why OKCupid doesn't like data-harvesting. Going around the rules in such an extreme way speaks of a lack of regard for other people's privacy and not really playing fair.
However, I'm impressed by his dedication and know-how. But on the other hand, it's very possible that he could have met his now-fiancee without going through all of that. It sounds like a very fun project. But it also sounds like he went all "mad scientist" on this. And that's not necessarily a good thing.
All in all, I'm fascinated by his research--but I'm also disgusted by it.