It didn’t take long for the discussion around the Boston Celtics to devolve into “ too many threes ” and “ split up the Jays .” Negative news sells, so the instant the Celtics don’t live up to expectations, those scripts get dusted off and, well, here we are.  Of course, there is always a nugget of something to hang onto that keeps these things alive. It’s not that there isn’t something to discuss within these conversations, it’s that they become the only argument, and it throws out all nuance and reason.  So with that, I’m going to tell you all the reasons why this notion of trading Jaylen Brown is wrong.  Before I do all that, I want to be clear that this piece isn’t an argument for or against trading anyone. Brad Stevens has a job to do , and everyone on the Celtics should be up for discussion in a trade that makes sense for the team. If Stevens saves R.C.…