More than a little dubious about this, personally. Payment by results sounds good, but the governments application of this premise so far - for example with the welfare to work programme and A4e - Has hardly been a ringing success.
It does rather seem ideologically driven, and a rather disguised way of cutting the cost of the service at that.
As for Grayling - He said something today in the House along the lines that the previous govt was obsessed with pilots - sometimes you should just give stuff a go - Well that might be a good attitude for, say a parachute or bunjee jump, or any number of one -off endevours in ones private life, but implementing wholesale changes to public services on a whim and without evidence is a recipe for omnishambles, in my opinion...
http://blogs.channel4.com/factcheck/factcheck-has-chris-grayling-unlocked-the-prisoners-dilemma/11879