There are two issues with this nonsense:
1. Only 313 people get a vote to whittle the runners down to two. After that only around 125,000 people have a vote to decide the winner. I can understand the politicians' eagerness to take part; any opportunity to get their mugs on the telly so that they can spout their seemingly endless drivel is always keenly taken up. But why on Earth should the TV companies feel the need to expose the rest of us to this ridiculous pantomime?
2. Even if this was a vote involving the entire electorate, how many people are swayed by an hour or so of uncontrolled bear-baiting? How many people base their vote on how well the contenders "perform" on such occasions?
The electorate has had enough of politicians in the past two or three years. Most of us just want them to get on and deliver the one thing of any importance that the voters have been been directly consulted on in recent years. That's all. After that they can return to their "Party Political Broadcasts" and other irrelevances that seem to occupy their time. Until then they should keep out of public view.