I'd argue that game theory could be tremendously more useful if its practitioners made a better habit of questioning their own assumptions about the situations

I'd argue that game theory could be tremendously more useful if its practitioners made a better habit of questioning their own assumptions about the situations they model. In the study cited in the article, the authors (seemingly) assume that pitch and play selection have constant or near constant marginal returns. That is, they assume that if pitchers just threw fewer fastballs, they'd be more successful. There is really no reason from the data presented to assume that. Perhaps pitchers need the fastballs to set up better pitches (they do), and perhaps other pitches wear their arms out faster (curve balls tend to). The author of the main article hints at this possibility in the context of NFL plays, but doesn't address it very seriously. In general it's dangerous to look at data without a solid understanding of the theory behind that data and then claim to have a better understanding of that field than those who operate in it vocationally.