Very tame for "going after" her. He knows he can't do a serious about face on it or Democrats will abandon him in droves.
He's always tame. That's the strategy, he introduces a line of attack and his $23 million dollar online astroturfing machine blows it up online for him. Then it circles back to him where all he has to do is say the magic words and his supporters and the media know exactly what they mean.
You mean like how Clinton says that she respects Sanders staying in the race every week, but 5 minutes later on the same network, her surrogates demand that Sanders drop out for the sake of party unity?