I agree a lot of it is in the delivery, and it does take skill to do that and not taking anything away from them - thats their talent. But what i'm saying is they aren't that funny without the script. Have you actually seen them off air? The interaction is there between them but not the clever lines - though a lot of the looks to each other are rehearsed to get the timing right. But the public (and i guess this is to their credit) mostly get the impression they are just naturally talking to each other on TV but i've rarely ever seen them do anything off-script. I guess thats where the M&W stuff comes in, a lot of people think they are presenting in a comedy style like the M&W show was.
IAC is the most scripted one out of the lot of them. Show has more writers than any of their others. They ARE just spouting other peoples lines, there is an element of them naturally bouncing off each other, yes. As above - they should be applauded for the delivery if anything.
it's almost like you are claiming M&W weren't scripted to the nth degree. Google them, please. They were fantastic but please don't run away with the idea that almost all of their funny interraction wasn't scripted to within an inch of its life.