The problem is, no one can quickly reverse the 14 years of mismanagement and neglect of the NHS. Leaving people languishing on waiting lists is good for no-one. If that means utilising the private sector for a while, then so be it. It is not ideal, there are pros and cons, but I am not sure what other option there is in the short term. It will take years to build up the staff numbers, equipment, infrastructure, etc.
Blair/Brown did the same and by the end of their term the NHS, while in no way perfect, was in good shape in terms of waiting lists, a&e wait times, cancer survival etc.