I went to the first Famous Dave's in Grand rapids a few years ago on their opening day. My girlfriend and I got the trash can lid for 2. Everything was awesome and we loved it and couldn't wait to get our parents and friends there.
My friend has a good theory that chains open with their pro chefs to get things going and training the people that are actually going to work the store, then move on. Possibly, they are getting better cuts of meat at first to get people hooked, then things go downhill from there. You would think the recipes wouldn't change and the food would stay as good as it was at first.
I don't know if any of that is true, but it sure adds up.
I have had mixed experiences at Famous Dave's and noticed this trend at Damon's (local rib chain/sports bar...all now closed), Logan's Roadhouse, etc.
I am not a lover of chain restaurants, but this is America now.
Thankfully, there are the small independent joints in town that have consistently good BBQ and I can always make the best stuff myself.