We did the DDP in '06/'07 & '08 and enjoyed it, but we made 1 TS/ADR for each day of our trip (including Crystal Palace, O'hana, Garden Grill, Whispering Canyon, Hollywood & Vine & Cape May Cafe etc). Coral Reef had outstanding service and we doubled the tip.
The bills averaged out to be $120.00/per TS for our family (2 adults & 2 girls under 10).
This year, the tip issue really frustrated us
because of the suggested amount and the service was not up to par the majority of the time.
Considering we always shared CS, (which cost less then $50.00 with drinks & dessert) which I considered to be big combos & had left overs, our next visit, we will budget $$$ for food, pay cash and honor good service.
CS have healthy food & a good variety and gives your schedule more flexibility with young kids.
Best bet is to take the time to calculate $$ on and off the plan to consider if it would be worth it and compare it to your budget.
Good luck