We had a party of 8 the last time we went. We were never directed to Group Dining for any of the restaurants we chose. I did, however, make sure to make all of our PSs well ahead of time.
The only 2 places where we were separated were Sci-Fi Dine Inn and Garden Grill. The Sci-Fi was no big deal - we were seated at 2 cars near each other. The Garden Grill was disappointing because we had to be in 2 different booths and could not even see each other. BTW, they do have booths able to accommodate parties of 8 but a group of 4 ahead of us decided to ask for that last particular booth and they were given it. When we complained that they didn't need it and we did, they told us that their policy was that they had to give it to anyone who asked. I personally thought that was bull. We won't be going back there. Not just because of that but because we weren't impressed anyway this time.
The best places were the ones that sat us at large round tables: Spoodles & Liberty Tree Tavern.