Here’s a quiz for you. What do the following numbers - 581, 331, 162, 62 - represent?

The answer is the number of accountable chief executives with statutory responsibility for the planning and commissioning of NHS services in 1999, 2002, 2006 and 2011 respectively. With further clustering of primary care trusts likely and the NHS commissioning board taking over from strategic health authorities in July next year, that number could dip to just below 50.

True, in some areas, nascent commissioning consortia are getting their hands dirty, but they will not be legally responsible for their decisions until, at least, April 2013.

Some of the clustered PCTs are gigantic organisations. Has any NHS commissioner ever had more spending power than the Greater Manchester cluster’s £4.7bn? Mike Burrows, that cluster’s chief executive, will be personally responsible for approximately 6 per cent of the NHS commissioning budget. A further 12 clusters have commissioning budgets of over £2bn.

The clustering of PCTs was a sensible response to the haemorrhaging of management capacity and the need to maintain a grip on the system as the demand for efficiency savings ramped up.

But there is a strong possibility that the clusters will be asked to take on a wider range of responsibilities for a longer period.

The listening exercise being undertaken into the government’s reforms is beginning to throw into contrast what is likely to change and what is not. In short, the basic architecture of the reforms – barring acts of Liberal Democrat self-immolation – will not alter. However, it is likely this new world will come into being slower than health secretary Andrew Lansley would wish and in more a graduated way.

NHS Future Forum chair Professor Steve Field places the emphasis on secondary legislation and, along with NHS chief executive Sir David Nicholson, the authorisation process for commissioning consortia. This is a recognition of (likely) reality, as Professor Field says it is changes “outside the bill” which will have the most influence on “how you would make things work”.

A very good example is the influence of hospital doctors and other clinicians over commissioning decisions. The prime minister has indicated this is an area in which he expects to see change. However, it is unlikely – and undesirable – that a legislative change would be made to insist that X number of clinicians, members of the public and so on should be represented on consortium boards. Professor Field is right to say that “tokenism hasn’t worked in the past [and] it won’t work in the future.”

It is also clear that GPs do not think it is a solution. HSJ’s unique analysis of consortium boards shows very few believe that this is the right way forward, with none of the 51 analysed offering a seat to a hospital doctor. They have, on the other hand, almost all recognised that management was an essential element of any board.

A more likely (and desirable) solution to involving other clinicians in commissioning is to make it a part of the authorisation regime that consortia involve the appropriate expertise when making decisions about services. Just as it would be sensible to require Monitor to make sure that the developing healthcare market made the best use of cooperation rather than writing into the bill, for example, that competition should never undermine providers.

But this, yes, evolutionary, approach takes time – and also requires careful oversight as well as someone to mind the knitting.

Which takes us back to the PCT clusters. Set up and staffed with one purpose and timeframe in mind – a rethink may be necessary to recognise both the length of time they (or something like them) will need to exist and, also, the power they will wield over that period.