[Edit: I have asked the wrong question—my apologies. What I am looking for is not a single word, expression, or idiom. I am looking for a parable or an example of an analogy. Maybe a one-sentence, real-life story of a well-known instance where megalomania meets idiocy.]
Occasionally people get excited over some business plan or idea in general, talking exaltedly about the outcomes or benefits, ignoring some crucial logical hole or contradicting physical laws.
Executive: Now if we get the response time for our signal to Australia below 50ms we have won.
Engineer: But the speed-of-light limit to Australia is 67ms.
Executive: Yes, it is a problem but we must not give up now.
Are there any canonical parables or examples of analogies for this concept?