Pat and other responders,
I get the penal flora that thick rough presents and it's ability to defend, and I understand its employment on Open courses as a challenge to the best players in the world. Never the less, I have concluded that the good Doctor was correct.
Deep rough slows play and overwhelms the average player. I think the most interesting courses employ cunning design, not rough, to challenge players. This is true at TOC, Boston Golf Club, Wolf Point, Rustic Canyon, Pinehurst #2, and other courses that employ hazard placement, green complex design, and width and fairway design, to create challenge. "Indifferent shots are punished, but recovery is possible" is much more fun and interesting to me than "find it, and gouge it out." In my mind the best courses defend themselves via what I outlined above, while giving players options for problem solving. Augusta National used to be this way, but some of it's strategy has been lost due to tree instalation. I am very sure that Dr. M would be upset by that.