As with most things, I think this goes back to the definitions you hold for the key word in the phrase. Here, "great" is the word that's the source of the question. A great golf course, to some, might be one that causes great players to seperate themselves. Historically, you could look at TPC Sawgrass, ANGC, St. Andrews, wherever has the long, distinguished list of past champions that we've all heard of and say that those are great golf courses. Others might look at the difference between the winning score and 5th/10th/20th place to determine greatness.
I'd argue the two have little, if anything, to do with one another. A great golf course, to me, is not defined by how the top .001% of players happen to play it on a given weekend. I'd also say the course the PGA TOUR plays is rarely the course that is there for the other 51 weeks of the year.
Semantics aside, whether this particular version of Riv was a great test of the complete set of skills required to play PGA TOUR golf for the players this weekend, I think you'd have to say yes because no one skillset seemed to be at an advantage.