I have had bad or less than stellar experiences at only 3 locations.
Le Cellier 2003 with the CP dinner package. The food was awesome, but the service was lacking. The service was overall way too slow and the restaurant was no where close to even being 1/2 full at the time. However at the end, the server without asking first yanked my plate off the table, which I was not done with, and said "All done?" to which I said, "Well, I guess I am now."

It took me 5 years to give the restaurant another try. I am happy to report that it redeemed itself. I had an awesome meal there last month.
50's Prime Time Cafe....ugh.....
We have given this place 3 times to redeem itself and it has failed on all attempts.

It's permanently off the list. The service was never the issue, but the food is just not good. I guess I know that I can make better food at home and for far less money, so it sort of taints the experience.
ABC Commissary
This place has been very spotty on service for us, but our visit in December sealed the deal. We won't be going back. The food had gone way downhill this time. The Cuban was just awful, which is a shame, because it used to be something that I looked forward to. The lack of options for my oh so picky partner also is a negative. Unless something big changes, we just won't be back.