Rule #2
You only get 1 table service credit per day: Many of our favorite restaurants are 2 credits for instance (Jiko, Flying Fish, Cali Grill, Citricos, Narcoossee, Artist Point, Yatchsman, Brown Derby, Le Cellier, Fulton's)
True, but you can use more than 1 TS credit per day or we often shared meals (see Rule 6) and were able to use our TS credits at 2 credit meals.
Rule #3
Not all menu items are included and you can't do any substitutions
It's true you can't order an appetizer in place of a dessert on the DDP, but you can sub some things such as side dishes. Your entree comes with broccoli, but you'd rather have the potatoes that are listed with a different entree - you can make this substitution.
Rule #5
No appetizer and some dinner items can not be selected from the menu
None of the entrees or desserts that are listed on the menu are excluded with the exception of the larger Kitchen Sink (Beaches & Cream), and usually the multi person dessert at T-Rex and Rainforest that I can remember. Items listed "for 2" can be ordered by 2 people.
Rule #6
Can't split a meal between people: for instance getting an appetizer and 1 main course to split between my wife and myself
We frequently shared one entree and dessert between 2 adults and used 1 dining credit or 2 credits at sigs. Sometimes we also ordered an OOP app, but not always.