University College London Hospitals foundation trust chief executive Robert Naylor said providers had come further than most foundation trusts thought.
While services had improved, producing better waiting times, the commissioner side still had to improve, he said. Commissioners had a 'thankless' task and were too often fragmented with the demands of managing GPs.
Mr Naylor said the sooner a split was made between providers and commissioners, the better.
Managers were also having to cope with a 'bureaucratic nightmare'.
NHS Partnerships chair Richard Jones said the overall direction of health strategy was correct - and the main political parties had a 'broad' consensus.
Department of Health strategy director Will Cavendish said he broadly agreed with the tenor of the debate so far. Reform to date had mostly focused on acute care but there needed to be clearer rules for turnaround and provider failure, he added.
GP and a member of the Colchester practice-based commissioning group Dr Shane Gordon said getting GPs involved in service design was crucial. But it was 'quite unrealistic' to ask GPs to divest their time into redesigning pathways without incentives such those given under the quality and outcomes framework.
Yet managers concerned about GPs being both providers and commissioners had to 'live with it' as it is an 'unresolvable'.tension.
It was important that practice-based commissioning was done in large clusters, he said, and that PCTs grew to trust GPs.
Mr Naylor said foundation trusts were not using their powers to the full, such as the ability to borrow. Choice and payment by results had not had a major impact on foundation trusts, he said. Yet choice presented trusts with a strong opportunity to 'sharpen up your thinking'.
Of all trusts, a third were at foundation status, a third were 'struggling' to get there and the other third had 'lost the plot' he said, with those in the bottom third failing to attract good managers.
Richard Jones, who is also director of operations for BUPA, said he expected use of the private sector to increase, but in 10 years' time would not be carrying out the majority of NHS provider work.