It's not Pat's mic to cut off. The producer is in control.
If it were actually Pat's show, he might have some say, but Pat's only sitting in for Scarborough.
Pat did a good job keeping his cool and letting the story unfold. O'Neill's story has been told and will be told again. Having a fellow "journalist" go bonkers on the air is an event one must let emerge. Cutting him off would only be protecting O'Donnell from the embarassment.
Don't get me wrong, O'Donnell will get big time praise from the hard left, but he's going to be marginalized now. The Nation types and DU types are going to elevate him as a favorite. But by the time this is over, he's going to have to go on a sabbatical before working "mainstream" again as anything other than a leftist pundit.
Especially if the blogosphere let's O'donnell's words speak and gets MANY more viewers than MSNBC had on a Friday night.