Here is some chatting I did with a blizz representative.......

you: Yes, I was banned because of this message: "no you fuckjin threw it by fightin 2v5 3 times" and I wanted clarification as to why this statement was ban worthy you: As you can see this is a statement as to why we lost the game with one curse word Syntharous: Why is it ban worthy... Syntharous: Well- Syntharous: It's a direct violation of our harassment policies. :) Syntharous: It's as simple as that. Syntharous: We of course take reactive action with these- we aren't searching for four letter words and then applying actions, we'll be going off of reports that are sent up. you: So if I had said "You threw etc" instead of the one curse word - is that still considered harassment? Syntharous: But that doesn't change the fact that a clear violation of our harassment policies was made. So, that results in the suspension. I wouldn't take it too personally- it's just a sort of reminder that you shouldn't use such language in a match if you want to be able to continue to play uninterrupted.
you: Ok, but I would like to know if I said ""no you threw it by fightin 2v5 3 times" is that harassment? Syntharous: Well, we would always look at the chat lines in context so it might be as clear cut as "yes or no" Syntharous: But the direct answer to your question is no, it wouldn't be considered a violation. you: Exactly my point you: That is why the mature language filter is an in game feature Syntharous: Because no four letter word was used (even if you mask the word, if it's obvious then we will action you for using bad language). you: But that makes no sense you: why have the mature language filter and get penalized when using mature language?