Commentary Writing is More than Unchecked Opinion
I love a good rant. Nix that. I love an unhinged, unreasonable, completely biased violent outpouring of insane opinion. In movies, plays, novels and even in person. Just not in my news commentary.
In fact, I would never put such an angry display in my own commentary writing, as much as I am prone to spew it for my friends' amusement. (They know me and how silly I can be.) That would be a discourteous waste of the reader's time.
Like a few who read this blog, I have a news commentary beat for Yahoo! News. While I don't always take full advantage of the opportunity, I am aware that the beat is a privilege and don't intend to abuse it by passing off vitriolic opinion as reasoned commentary.
Reasoning is exactly what should be behind and shown in good commentary writing. Never let the reader suspect you've been nipping at the crazy sauce.