Never underestimate the Pavlovian tutorial that is growing up in the South. I still say yes ma'am, no sir, thank you and please to anyone that might conceivably be my elder. I hold doors open for people. I moderate my language around people I don't know well. It's just ingrained in me. That courtesy is necessary for success in the publishing industry.
For example--last year one of my editors came to me with a problem author. At first I couldn't understand what the problem was. Then I opened the manuscript. If the writer disagreed with the editorial change or suggestion, he left snide, nasty, rude comments in the margins. I mean REALLY rude comments. This author had a bachelor in the 1880s American West living in a 'pioneer' cabin with running water AND a sofa. So because it was that editor's first book with us, I took over the edits, letting the author know that his ability to go through the editing process like a mature adult was the thread upon which the publication of his book hung.
Guess who didn't stay with us when we moved the imprint to Musa?
Writers should inherently understand the power of the written word. After all, words are the tools we use daily. And yet, every time I see an author behaving like an asshat online--bashing their agent or their publisher, whining about their edits, or worse--responding rudely to a legitimate review or critique--that author's name goes onto my mental "Do NOT Publish" list. You know--I can't remember my phone number half the time--but I sure as heck remember the name of an asshat writer.
So think carefully before you hit 'send'. Make absolutely certain that what you say can't come back and bite you. The best response to a vicious review? None. Tweet about your cat or your word count or your favorite football team, but don't be stupid enough to bash your publisher or editor or agent in public. Take that energy and funnel it into something productive.
My trick for that? I create a character in my WIP that's mentally tagged as whoever has pissed me off. Then, I kill them in the most cruel, vicious, disgusting fashion my fertile and evil little brain can cook up. Then, when I see that asshat anywhere else online, I can just smile quietly and move on. "Thank you" and "Please" and "I appreciate it" will get you a heck of a lot further in any business. Employ those words and the intentions behind them frequently.
Trust me when I say that--if you're on one publisher's DNP list, you're probably on quite a lot of them. It's never a good thing when the only thing between a writer and success is the writer.