Mr. Daley,
Your last post has prompted me to enter this debate, although surely I'll regret it.
While I have not yet played Black Rock (although I look forward to an invite), I do travel to Coeur d'Alene several times each year (where the in-laws live), and can attest to the genuine beauty of the area. I sense that you have not been there, so I encourage you to stop by on your hypothetical drive to Seattle. If you do, you'll find some pretty good courses besides Black Rock, including one of my favorite "cheap eats," Indian Canyon in nearby Spokane. Also nearby is The Coeur d'Alene Resort Course, a venue that is often criticized here but nonetheless worthy of a round if you're within 100 miles. Also, just South of Black Rock, is a newer course, "Circling Raven," which is a tough test of golf when the winds are funneling accross the "Rolling Palouse" country.
As for your hypothetical, in the "real world," the ratings are but one source of information. I would also take into account the advice of others whose opinion I trust, including GCA Doyens who have played at least one but, even better, both courses. In other words, for me, I'd look at the ratings in making my choice, but they are certainly not the final word.