Just curious what you mean by saying it wouldnt be fair? Even comp play allows this sort of thing. There should be no downside to team communication.

I assume youre referring to times like when a spy is on a stabbing spree or something? Most pub players dont pay any attention even if youre screaming about the spy anyway. The good spies still seem to get away, regardless.

I think being able to communicate about flanks and what guns are down far outweigh any of this. It will improve the overall game play and encourage more people to communicate.