When it come to watching news programmes that compete directly with each other, like the BBC and ITN bulletins at 10 o'clock on weekday nights, I've long thought that ITN's deloyment of two news readers works better than the BBC's preference for leaving the whole thing in the hands of a solo performer - for two main reasons:
1. It dilutes any dislike of a particular performer
If you're not too impressed by the BBC's Huw Edwards, it's tough luck: like him or hate him, that's who'll be reading the news for the next 25 minutes - so your only available escape is to switch over to ITN, where the likelihood of two news readers both turning you off is obviously considerably less than when there's only one of them.
You might be a fan of Julie Etchingham but not particularly like Mark Austin (or vice versa). But at least you know that, for about 50% of the time, you'll get relief from whichever one of them you don't particularly like.
2. It helps to keeps viewers on track
People don't watch news programmes so closely that they always know when one story has ended and another one has started. Nor is every story of equal interest to all of us.
When there are two readers taking it in turns to deliver different news items, you can tell at a glance when something new is coming up. If your concentration has lapsed, the other face and/or voice alerts you to become more attentive again, if only to check on whether the next story sounds any more interesting than the last one.