Melvyn,
If there was a business feasibility plan, I think BD and SH would never have been built. Fed Ex would also never have gotten off the ground, as its founder actually got flunked on his business plan in college. Actually, those who do feasibility studies are usually accountant types by nature, with little real vision, if I may generalize. There are some different personality types out there and one is "designer-developer" which is quite distinct in trying to take chances.
As for gca's doing feasibility, it is generally seen as a conflict of interest. What gca wouldn't have a tendency to say "sure a course would work here" if a design commission is at stake? Yes, I know you think we should all be perfectly pure, but someone will design a course for an owner and if we think we are the best, we tend to think we will do it the best for that owner over someone else. There are only a few hundred "perfect" sites in the world.
And, most commissions aren't for dream projects, they are by definition the best course for the real estate, muni, etc.
There have actually been many threads about whether gca's should turn down jobs. In general, the answer is no. We are professional gca's, not hobbyists like George Thomas or CBM. Its just the way it is, and there is nothing evil about being paid to design a golf course, or trying to provide what the owner wants, or anything else that goes with it.