"Once they had some working theories, they figured out a system for interviewing managers to gather more data, and to look for evidence that supported their notions."

Oops. That's called confirmation bias.

http://www.sciencedaily.com/articles/c/confirmation_bias.htm

http://www.skepdic.com/confirmbias.html

Did they also look for evidence that cast doubt on their notions? Looking for both kinds of evidence, and evaluating them fairly, would lead to a more robust conclusion.