When a client gets into a dicey situation on Twitter, sometimes the best plan is simply to “zip it" and say no more. PR professionals understand this intuitively, but many have clients that do not. If a client doesn't understand why you're telling them to zip it, they may ignore you and follow their gut instinct to explain themselves (got ‘em). Even if they have the best intentions, that can make things worse, so I thought I’d try to explain where the "zip it" advice comes from in a way that anyone can understand.