Plans by two Scottish councils to work together to save money will lead to confusion and harm vulnerable people, according to public sector Unison.

But that can only be the case if you assume the strategy is implemented out with a huge decree of incompetence.

The suggestion is that each council becomes the 'lead' for a key service. Clackmannanshire will run social care services for both councils, while education services for both will be delivered from Stirling.

The history of shared services in Scotland's councils is not an encouraging one. Plans for eight Clyde Valley councils to run many services jointly foundered when South Lanarkshire, Glasgow and West Dunbartonshire pulled out.

East Lothian and Midlothian had planned to merge many departments but have reduced the scope and pace of their plans. Even Stirling and Clackmannanshire's 'lead provider' approach was first announced more than two years ago.

So perhaps the union is right to err on the side of pessimism. But Unison's concerns, which are based on a survey of staff, are speculative.

The union's members claim that once the 'lead provider' scheme is up and running the public will not know who provides their services or how to find out whether they are entitled to help.

This will be so only if the arrangement is badly handled or explained. But that is more an argument for good planning and communications. The same applies to the complaint that council staff will be 'confused' about which policies to follow from which councils. It need not be the case if the councils explain sensibly to employees what is happening.

A third claim that people will be confused over who provides their services achieves a double whammy of assuming the worst about both the councils and the public.

Members of the public do not need to be patronised over such matters and many will see the common sense of reducing a duplication of costs for each council.

Indeed, the developments at Stirling and Clackmannanshire are surely an indication of the shape of things to come. Councils facing drastic spending cuts, as we know. Some now need to repeat savings achieved over the past 5-7 years, but this time over the next two. Many English councils have already made savings twice the size of those proportionately achieved by their Scottish cousins.

Maintaining separate services within a council the size of Clackmannanshire has long seemed a luxury but the wider case for shared services may become unanswerable. Is there any reason why a relatively uniform service such as education should not see much of its administration run on a national basis, for instance?

Scotland's police and fire services have been brought together under single bodies to achieve savings and efficiencies. It is important that local political accountability is maintained and where there are genuine concerns about the impact on frontline services, unions should make their case. But they must also be willing to play their part in finding solutions to the extremely challenging circumstances facing councils.