It's pretty obvious that:   “one shall be taken, the other shall be left.”

If the project is “vague and impossible,” it might be “a wart on the project plan.” In other words, it has become a task that (a) may no longer have a (pressing) business requirement, and (b) at least represents a lot of sunk-cost until someone can figure out how either to defer it or to get rid of it altogether. “But the good news is,” as someone is surely saying in a high-level meeting, “at least we know there is a sure-fire way to cut costs by 50%.”   .. .. ..  :-/

As an aside:   this is one of the best threads I have read anywhere in a very long time, and it's a link to a great many other older threads that I never knew existed.