Actually, stopping at "cui bono" would be a great thing. The common pathology is that people start with the legitimate idea of who has benefited, get hung up on unsupported specifics, and end up creating straw men that then get used to discourage talking about the obvious incentives.
No, the common pathology is that they stop at cui bono and come to conclusions about facts based only on incentives instead of empirical data and evidence.
