Thanks - this is a good idea but would never fly in the culture we have. It's a very casual and relaxed kind of place and the last person that held a job close to my own was very ineffectual and basically did what other employees told her.
I challenge yoru assumption. I think you *do* need to shut them down.
Maybe you do it more nicely, and maybe you create a one-on-one with this particular guy.
And maybe you say, "i know te person before me was a pushover for you, and basically all you guys just told her what to do. I have a lot of experience, and all this commenting on my job is getting in the way sometimes.
"If you have something you want to tell me because you think it will help me do my job better, email me and we'll speak in private in the conference room. Do not comment on my work or crtiticize me in public anymore.
"But if you stop and think about what you said to me, you'll realize that you didn't add anything of FACTUAL substance that I didn't already know. Mostly you vented about your personal opinion of somseone--that's not profession. And while we have a collegial atmosphere, that sort of input doesn't help.
"And here is the standard I want you to apply. Is this your personal opinion? Or are there *facts* that I'm not aware of. I'm aware of the size of hat market and circulation. "
And then have a cut-and-paste response. "If you have factual information to give me, you need to bring it up to me in private."
Time to shut them down, to be honest. Sure, it'll be a shock to them. But they'll get over it.