That's the thing though, going off of this quite it doesn't sound like including split screen would've affected single player/online multiplayer. They just didn't want to add it because it'll look too shit as split screen for their standards.
same with cod. I personally wouldn't care if there had to be some technical sacrifice to get splitscreen as long as it is independent of single player.
What they were saying is that they were unwilling to compromise on the graphical vision in order to accomodate split screen at 60 FPS.
The Mario Kart example says that adding it does drop the FPS.
I said that I'm expecting they're going to start with a target of 30 FPS, so they can't really drop below that, meaning their only option to have a stable framerate for split screen is to reduce the graphical quality, thus allowing it to be rendered multiple times without a dramatic hit to the framerate.
Basically A to B to C says to me that the graphics in games that have split screen either have graphics that are not as nice as they could be in single-player due to never having to deal with rendering it twice over, or they choose to take a framerate hit when doing splitscreen.
Regardless, we're arguing over a theoretical mode that likely won't exist.
I remain convinced that such a mode will lead to a diminished single player experience. You do not. Neither of us is going to change our mind.
I think we've hashed this out enough and we can move on.