I'm no Rosie fan...but having a pissing contest with the likes of her...whether or not he "wins" or not doesn't matter. Of all the people he could trade barbs with...she's a comedian, he's not. He'd be doing himself a big favor by just letting it go and letting Rosie continue to make an arse out of herself.
Besides, she has a great catfight going on with Bah Bah WahWah