The best data is just hard to collect online. Photos of person in their social group to deduce personality type would probably fail since there are so many variables. Lab scientists can measure biological or physical properties http://www.youtube.com/watch?v=XGfznq9OgdU&feature=playe... like sweat scent which reveals immune system compatibility. They're getting very good correlations for long term relationships from…
The fact that there's so many variables isn't the reason such an analysis would fail. The reason is that there's just not enough input to predict personality type with any statistical significance.
There's just so much that could be measured, but whether any of these metrics have any correlation with whether two people can, as the author describes, "just get through dinner" is a very tough question to answer.