User blog comment:Deathmanstratos/Some Call of Duty: Advanced Warfare singleplayer background information revealed/@comment-5290320-20140504234906/@comment-1187559-20140505001148

Well given the nature of FPS games it makes sense to not talk during the missions. I mean in Halo 1-3 MC didn't speak during the playable sections, that I recall, but it still worked just fine.