Matt;
Alright, fair question.
Admittedly, my grade of "7" on the Doak Scale is probably better voiced as a "7" on the "Golfweek" modern scale. I'd still argue it's a Doak Scale 6.
I will answer your question with a couple of words, since I'm trying to get out of here to actually "play golf" today!
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I thought the attention to details was superb. Although much of the earthmoving was for effect, much of it "ties in" to fairways, greens, and other playing areas in a way that is both intriguing and challenging.
I thought the course was "daring"! Holes like the 9th with the hyper-extended false front are original in concept and execution. I understand that when Tom Watson played the course on opening day, he hit his 160 yard approach with a 2-iron, running the ball all the way up that slope and stopping within 20 feet!
You mentioned several other holes that impressed you, so it can't be all that bad.
In comparison to Shoregate, the artificial features compounded to add to the excessive penality of that course. At Cassique, they may distract the eye, but also more often are used to create fun and interesting shot values.
Bob Crosby;
The River Club is a good Tom Fazio course. I liked Cassique a half to full point better, however, due to its daring distinctiveness and interesting shaping.