I don't mind having separate credits for children and adults, I think that's sensible and fair. But if the credits are actually *individualized* (that is, assigned to each person individually), I would hope that in non buffet, non all you can eat restaurants, that I would be able to order a three course meal and share it with my husband who is not ordering anything.
We honestly really don't need 2 three-course meals at one time! We would, however, go back to another restaurant later in the trip to use the other credit -- and each time we're in a restaurant, that's an opportunity for Disney to make more money from off-plan purchases, like extra drinks or alcoholic drinks or children's meals for under 3s who don't have credits to use, etc.
This is our plan, acutally, for group meals too -- each couple/room will start by ordering one complete credit meal, the couple with a 4yo will order a separate children's meal on the DS's credit, and we will share it all around.
As for individual credits, I think it makes sense to pool the credits and keep them 'per reservation' -- or allow any adult in the room to use another person's card. It would be foolish to have an entire family stand in line for one or two CS meals, and difficult to keep kids entertained. I want to be able to send someone to the CS line and others to get/clear/set up a table if one is available (We'l need/prefer two highchairs and possibly a booster seat).