There is a simple thing to do "post as if you aren't wearing any signature ad and you will be safe". I think this is a simple thing to understand & apply, or maybe I am wrong.
Well, I don't think it's true.
Wearing a signature ad is what everyone is getting as a benefit for their account and posting. If that won't be allowed and there's a cap (which ain't as said by the Mod), then the signature space will be of no use and so, most people won't cross their limits posting too much.
But, all that matters according to me is the
"post quality, not just that, but it should be to the extent of your account level"... That's what came to my mind.