Delusional Project Management

The Diagnostic and Statistical Manual of Mental Disorders defines Delusion as follows:

"A false belief or incorrect inference about external reality that is firmly sustained despite what almost everybody else believes and despite what constitutes incontrovertible and obvious proof or evidence to the contrary. The belief is not one ordinarily accepted by other members of the person's culture or subculture."

I have seen a number of examples of Delusions in Project Management. One example from a while ago was a client decided while they could not do Project X which had medium complexity and would take 12 months, but could do Project Z that included Project X but do it all in 6 months.


Clearly individuals who are not clinically delusional can gather together into a team and collectively be delusional. I am sure there are many examples of such behavior.


What I am wondering is are there good methodologies for doing organizational psychotherapy to help such organizations and teams perform better?