Spyglass would probably be the first course I'd drop as well, along with WFE. Its on the list because its one of the shortest (under 7,000 yards) courses on the GD top 100, yet the resistance to scoring numbers indicate that it is one of the toughest.
If its not the length of the course that makes it hard, then what is it? Does Spyglass play longer because of the relatively "heavy" air at sea level? Does the normally temperamental NoCal weather make it harder? Or does it all come down to the fact that the course is downright penal, due to its combination of trees, water, well-placed bunkers and ice plants and the demands placed on the golfer to execute certain types of shots.
If its difficulty is due to its design, I think there is something of interest worthy of study in whatever makes this short course play harder than many of the beasts in the rankings.
Contrast Spyglass with Shadow Creek, another "resort" type of course. SC ranks as the 13th longest course (on the GD 100) on a per-shot basis, but if you look at the resistance to scoring numbers, it comes out 79th out of 100. So despite being long, it is considered relatively easy (at least compared to the other highly esteemed courses). Read into this what you will, but it suggests to me that the design at Shadow Creek does little to exacerbate the overriding concern of overcoming the tee to green distance.
Just some tangential thoughts, but there are some logical extensions buried herein to the distance debate.
Sven