The cost of completing the metric changeover

Opponents of completing metrication often cite the cost of the change as a reason for abandoning the programme. Undoubtedly, there will be costs as well as savings, but no reliable figures have been produced by independent bodies. We can therefore only make tentative statements as to the true effect. What is clear is that:

much of the cost of metrication has already been met (in terms of industries redesigning products and retooling factories, retailers investing in new scales and computer systems, redesigning the school curriculum, etc.)
some of the costs already borne are being wasted since the programme has ground to a halt, and its benefits are not being fully realised (e.g. the generally imperial environment prevents children from using their metric knowledge when they leave school; unable to use it, they lose it)
dual pricing and labelling continues to have significant costs, as does the retention of both metric and imperial package sizes
there will be one-off costs for converting speed limit signs - mainly because there must be a rapid changeover - but the replacement of distance signs can be spread over a longer period (as in Ireland) thus combining normal wear and tear replacement with metric introduction costs
postponing the changeover still further will increase costs in real terms
the medium and long term financial and economic benefits of completing the programme will far outweigh the short term costs - in terms of easier calculation, reduction in mistakes and misunderstandings, economies of scale, etc.