http://metro.co.uk/2013/11/05/call-of-duty-ghosts-mark-rubin-interview-there-are-things-that-were-not-allowed-to-talk-about-4173810/
GC: So the obvious assumption from all this is that the PlayStation 4 is definitely more powerful than the Xbox One, is that true?
MR: [acting very embarrassed] I can’t answer that.
GC: You can’t answer it on a technical level or because you’re being diplomatic?
MR: Can’t answer that.
GC: You can’t say whether you’re avoiding the question for diplomatic reasons?
MR: [embarrassed] I just can’t say anything… GC: Are the console manufacturers leaning on you to avoid these sort of questions?
MR: [unsure - speaking to PR guy] I don’t know if that…
MR: [even more embarrassed to us] Yeah, there’s things that we… We sign NDAs with the first parties [i.e. Microsoft and Sony - GC] and there are things that we’re not allowed to talk about.
GC: So when John Carmack and Shinji Mikami say the Xbox One and PlayStation 4 are almost identical, is that something you could agree with?
MR: Hmm… I would say that’s a bit inaccurate but I wouldn’t be able to tell you any detail of why that’s inaccurate.
GC: For diplomatic reasons?