Glenn,
I may just need to play it again, I love The Golf Club, which while different in some ways, is still old-style Pete Dye and has a lot of similar themes. TGC definitely has a better setting then Crooked Stick with more terrain and no homes, but Crooked Stick is pretty solid.
I'm sure the 46 spots is not a record for a four-year change. The GD list changes quite a bit sometimes from list to list. Its a significant drop to be sure (and I didn't rate it having not been there in the last ten years).
Certainly nothing says it cannot return to the list next time around either, it is not unprecedented for courses to fall off then come back a couple years later.
Edit: Oh, and Crooked Stick is admittedly MUCH better than your favorite course in Nashport, OH. What's that one called again? I still like that course, but just had to get that in there