Being annoying isn't a "legitimate strategy", you're just being annoying
Every time one of the two annoying player habits is brought up ("gg ez" or taunt spam) there's always going to be that one person who says something along the lines of "It tilts the enemy, why shouldn't I do it?"
This would be actually be a legitimate counterpoint (a low blow but legitimate) if you couldn't mute both all-chat and champion voices by default. Well, with a few rare exceptions (Blitzcrank's laugh makes some robot noises even when his voice is muted e.g.).
All you're doing by saying stupid things in chat or spamming ctrl+4 is encouraging people to mute both permanently. Denying people the possibility of encountering a friendly enemy player or enjoying the champions' voice lines. The only reason you'd do either of those things is if your goal is to deny people those possibilities. So. Thanks.
Edit: Anyway, thanks to all the people who stood up and called it legitimate. It proved my point perfectly and please read what I say next time.
D: