A study into the feasibility of a car ferry service between Gourock and Dunoon, on which passengers but not vehicles are subsidised, is the latest chapter of a tortuous saga involving taxpayer subsidy, private enterprise, viability, public service and politics.

The Scottish Government has spent £50,000 of taxpayers' money on the new research in response to complaints from residents in Dunoon and the Cowal peninsula over the quality of the passenger-only service introduced last year by Argyll Ferries, a sister company of the publicly owned CalMac. This service was the result of a decision by Transport Scotland to end CalMac's vehicle and passenger service, following a ruling by the European Commission that subsidising the carrying of vehicles on this route would be against state aid rules.

There have been decades of heated debate over CalMac getting aid for passengers travelling on a car ferry, while the private sector rival the Western Ferries received no subsidy. It has been difficult territory for the SNP, which said before the 2007 Scottish elections that two new CalMac ferries would be built for the route. These have not materialised and there have been complaints about conditions, especially in wet weather, on the passenger-only vessels which are now the only ones operating between the two town centres and the link for passengers catching trains at Gourock for Greenock and Glasgow. Western Ferries, although popular with drivers, operates between points a couple of miles outside both Gourock and Dunoon.

How to finance ferry services to Scotland's island communities and west coast peninsulas remains a difficult problem. The European Commission has recognised the need to subsidise lifeline services to islands. However, the Inverclyde-to-Cowal route fails to qualify because it is designated as a river crossing and there is an alternative, although lengthy, road route. For commuters between Dunoon and Inverclyde or Glasgow, the ferry is an essential service.

According to answers provided to Jamie McGrigor, the Tory Highlands and Islands MSP, the new research shows little difference in the reliability rate of the Argyll Ferries sailings between the two town centres and Western Ferries' rate. If that is the only question under consideration, this is clearly a waste of taxpayers' money. However, Transport Scotland argues that the purpose of the research is to establish whether a ferry service receiving subsidies for carrying passengers could also carry vehicles on a wholly commercial basis.

This is an acknowledgement of the considerable dissatisfaction with the current Argyll Ferries service for foot passengers. Having ended the vehicle and passenger services once cross-subsidy was ruled out, however, it is difficult to see how CalMac could make an economic case for reinstating it unless new financial factors have emerged since June last year. It is to be hoped that new, alternative possibilities are being considered, otherwise it will be difficult convincingly to rebut the charge of wasting taxpayers' money by commissioning a study to which they already know the answers.