So our roast dinner -
The two legs went on two plates but some of the thigh meat stayed attached to the bird so didn't make those plates.
I had one wing and a bit of thigh meat, about two tablespoons full.
Most of one breast on another plate, 2/3 of a breast say.
About half, or slightly less a breast on the last plate (and half of that wasn't eaten so the dog had it).
We also had two or three golf ball size potatoes each.
A large spoonful of carrots, broccoli, green beans and red cabbage, so four spoonfuls of veg.
And about half or quarter a roasted onion each.
We would usually have stuffing but didn't that day because I didn't have any sausages.
The food is all put in dishes on the table so people can help themselves to as much or a little as they like. The only thing I ask (which is ignored) is that they only put as much food as they'll eat on their plate, they can always get more if they want.
I don't think that's an unreasonable meal, it's a full plate.
This left about a litre and a half jug full of chicken meat that I picked off. Probably about third of that was shredded and cooked with peppers etc for the fajitas. I think the meat is better shredded through as you get bits of chicken everywhere without any big dry chunks. I didn't have any so this fed four. We all usually have one big fajita each, sometimes two. I don't think any of us have ever had three but people can have as many as they want.
Didn't watch the kids make their sandwiches so couldn't say how much went in, one might have had loads (by our standards) one might have had hardly any. They all put salad veg on the sandwiches usually although have to admit, I didn't see.
This leaves just over half a litre of chicken which went in the pie with almost a whole pack of bacon. Pie also had leeks and mushrooms. This was served with veg and fed five.
The 'risotto' was made from the stock from the boiled bones with chicken skin 'crackling' on top (Jamie Oliver tip). I had one portion of this when the others had fajita, two portions when in the freezer.
Dog had white grizzly bits and that dark livery bits inside the rib cage as I didn't want that in the stock.
I don't get the outrage about my chicken use!
Oh and for the person who asked, yes it was organic, it was from the farm shop. 
And KFC I have a two piece meal but don't usually finish all the chicken.