In answer to your orginal question Humbers, no, there isn't an agreed on rules for the way we moderate posts.
We, along with you all, follow the sites rules and regulations, but we do remove/suspend/ban on our own discretion too. Do we sometimes get it wrong? Sure we do, we're only human after all (with the exception of Chucky maybe), but as a rule we try to to over police the site.
Personally, I wouldn't have removed the post, unless it got nasty of course, but that doesn't mean to say another mod did it instead, as I've said, it could've just been an auto remove thing as it was reported by other users.