His analogy is Call of Duty as football, and next season they decide to trim team sizes and let people play with their hands - people wouldn't like it. Call of Duty is 'first-person > gun > shoot'.
No one's going to like a sudden break for a dance number or having to make sure they buff their handgun accuracy stat while managing aggro. Pffft - nerds and their math.
"There is the obvious truth that if this were football, and next year they decided we only want seven players a side and you can use your hands, I don't think people would want to go to many of those games," Mark Rubin told .
"So we can't change too many of the core rules, and the core rules are really simple. You're a player, it's in first-person, you have a weapon in your hand and you run around shooting other people."
Infinity Ward isn’t completely arrested by the very rules they themselves created so long ago. "We can play a lot with the outside of how that works, and it's things like character customisation, making the movement through that world better, making the world itself more interesting, adding the new modes, adding the new dynamic maps," explains Rubin.
"So there's still I think a lot to do," Rubin insisted. "Anytime we ship a game - and this a non-Call of Duty statement, this is any dev you've ever talked to - is there's always a ton of features they wish they could have gotten to, before they shipped. So I think we'll always be able to bring new and interesting stuff. It's literally that we're just trying to make a better game than we made last time."
"Giving people new content, new ways to play, Squads is a really new way to play that I think people are going to find really interesting, because it's different to anything we've ever tried to do in Call of Duty... I think we're going to continue that trend." Infinity has introduced destructible elements within multiplayer maps now - although it's no 'levolution'.
Call of Duty: Ghosts releases on PC, Xbox 360 and PS3 November 5th.