Yep, that is the full cliche. I assumed with republicans the instructions would not matter. Their ability to f__k things up is proportional to the number present. News media time is an exacerbating covariable.I think you mean this:
70 Republicans couldn’t pour piss out of a boot with the instructions written on the heal!! (that's what my Jr. High basketball coach would say way back when they could actually kick your arse for being a dumb shit).
