I appreciate that this is turning into a pretty slow discussion between you and me Rob, with the occasional linked or otherwise interjection from Yeez. But, I'll continue.
Interesting idea Rob. Are you saying we should be more like China? You're probably not... What you do say doesn't sound ideal for now IMO. The government of technocrats would necessarily be narrow enough in it's encompassing of political leanings, in order to achieve consensus on important issues. Because of this, it will effectively be a dictatorship, albeit one that lies in the middle between left and right. Although, this could be workable, IMO it would throttle views to the right and left, as well as any reactionary and dynamic views. In Britain's current political landscape for instance, this world mean that the likes of the Greens and Ukip, and even blue Tories and red Labourites, would not have a voice. Is this healthy? In some cases possibly. In others, it could be prove to be a bit of a loss.
In my view, there are subtle differences between centrist parties in the west. It is often good for a country to alternate between these periodically, in order to redress the imbalance created by one side or another. The people on the left and right of each side are there to remind the majority not to get too comfortable in the middle. So, although not prefect, it may be an idea to carry on as we are for now?
Look. I admit this hasn't been thought out very hard but I think there's something to consider rather than dismiss out of hand. You, for example, mentioned green politics. It's entirely plausible that my putative model of governance would lead to some green policies being adopted if there was evidence they were beneficial. And yes, there may be a certain amount of dictatorship involved. If food air miles are undesirable, is it really acceptable to fly in grapes, even if everyone does want to eat them?
As it happens, China was at the back of my mind. Government in China appears to me to be for the benefit of the middle class and the party rather than benefit of the people but would China be such a bad place to live if there was freedom of expression, human rights and open government added to what they have now?
Possibly, the answer lies with Technocrats dealing with the stuff that is testable while politicians deal with everything that is left over (I'm thinking of Bank of England contolling interest rates as an example).