I love his courses, too. In fact, the second hole at the quarry at Giants Ridge is almost a direct "lift" of his 11th at Tobacco Road. The first tee shot at Tobacco Road is pretty intimidating, but not if you hit it far enough, only if you hit it about 220, if memory serves.
For good players, in general, if you show the way to go, they are comfortable. For them, Indecision = Uncomfortable. As Tony says, if you know a blind hole, you can pick a line and commit. So, what makes it hard to commit to a shot?
Some tour player say things like Brian said - no defintion and wide fairways. That need for definition is what makes Pete Dye NOT use fairway bunkers on his cape holes - it makes them harder to judge w/o visual markers. He also uses 10-20 degree angles. 30 or more would be more clear to the golfer.
Some cite Augusta 13 (before fairway narrowing) as a good example. With 60 yards of fairway and a small creek, they would feel like an idiot going in the hazard. Thus, as the week goes on, they aim farther and farther right, self negating the advantage of the hole. (Not that it matters as much with modern distance)
An interplay of staggered hazards on either side of the fairway can trouble them, if they have to aim at a reachable target bunker and curve it around a carry bunker. They ask, what if it doesn't curve?