We often split meals at Disney (and elsewhere too). Of course, not at fixed price places, though. But I usually make our ADRs to take this into account and only select a la carte type places. For our family (DH, me, and 2 DD teens), 4 full meals is just too much. Depending on where we are and what people want to order, I may share a meal with one of the girls or the girls may share, etc. Sometimes we get 3 meals and an appetizer, etc. Sometimes we only get 2 meals if we know they are big portions. We have never had problems doing this.
Here is a list of places that we have shared at Disney with no problems. (These are all non
DDP, since we haven't done that due to our eating style)
Sci Fi (DH & I shared steak sandwich - he ordered chili app too) (Girls shared ribs)
Beaches and Cream (the 4 of us shared a chicken sandwich meal and a burger meal cut in half and then all shared a fudge mud slide)
Mama Melrose (DD & I shared chicken parmesan)
Kona Cafe (DD & I shared the terriyaki steak meal)
Yak & Yeti (DD & I shared the steak & shrimp meal; other dd just got potsticker appetizer)
Rainforest Cafe (DDs shared steak, ribs & shrimp trio; I ate the free appetizer that comes with safari club- pita quesadilla)
TRex (I ate an add on ribs that we ordered with someone's meal and shared fries with DD who got a burger) We really should have only ordered 2 meals here because it was a lot of food and we still had lots left over with only ordering 3 meals.
That's all I can think of right now.
Maggie