I usually lose 10 - 14 lbs. on a 9 to 10 night WDW vacation. However, I usually graze throughout the day, eating a table service meal every two or three days. I don't limit my food selections, except I do try to watch my sodium intake a bit.
In October, 2006, we were at WDW for 10 nights (checked in 09/30/06--last possible date!) and lost about 8 lbs. on the free
DDP--with appetizer. We did try to dine earlier in the evening--between 5:00 and 7:00 p.m.--even though we rarely called it a night before midnight.
Now if I could only maintain that weight loss at home! *LOL*