Well, Hannity (conservative, clean cut) and Colmes (liberal, face for radio) split their time with interviewees, and whoever is second has to be pretty agressive when they cut in. It's offputting, but necessary.
My guess is the network dislikes Colmes but wanted to appear fair by allowing another point of view. D Miller does it on his show. I don’t know why. It’s not news. It’s commentary. I rather chew my fingernails to the soft tissue underneath than hear a bunch of liberals spout their idiocies. I get enough of that on the fake news.