In all seriousness, PJ has a point....not just anyone can sit in the chair and do what the team does each week.
I was on a radio show a couple of months ago, just me and the host, and we only had 45 minutes of time to fill, and it took every bit of effort and prep to fill just that time alone. And that was a one-time shot...not weekly.
The team could pick the best 5-6 posters from the DIS Boards, tell them they're gonna fill in for the team on an upcoming show, give those posters a month to prepare, and they still probably wouldn't be able to pull it off very smoothly.
It's not just Disney knowledge, OR personality....it's actually the art of conversation that matters, too. And not everyone has that.