There is an old saying. Not sure if this is the right wording but google puts it as "talking is silver, silence is golden". It is better to not say anything to your opponent after a humiliating defeat in Crucible than typing a "gg" via a message to them. You will, in most cases, just make them even more angrier at the game or your team. Surely I am not speaking for anyone but myself. But think about it. Defeats in Crucible can be very frustrating on a general basis. For example my recent situation (and why I make this post): Saying "GG" after a stomp match that goes 5-0 or 5-1 in Trials is basically for the people on the loosing team in most cases like pouring salt into an open wound. You are only hurting their experience more with that, unless they are very tolerant with defeats in this game. I recommend to say "GG" only in appropriate cases. A humiliating defeat is not such a case.