Of course the present Prince of Wales will become Head of the Commonwealth at the instant of his mother's death, simply by the fact of becoming King of the United Kingdom.
That that is not quite technically how it works is one of those little quirks which are in fact the point both of the Commonwealth and of the monarchy.
Indeed, the Commonwealth and the monarchy are very largely the point of each other. What else is either of them really about?
In any case, the monarch's and the Commonwealth's schedules are too integrated for anyone else to do the job.
Who, exactly, could that other person be, anyway? Who else would even want to be the Head of the Commonwealth?
Meanwhile, paying a British shipyard to build a new Royal Yacht would be an admirable use of public money to stimulate the economy by providing unionised, high-wage, high-skilled, high-status jobs to working-class men.
The trade that the Yacht itself would bring in, would recoup the cost of building it many, many, many times over.
John Redwood may dine out on his opposition to the Major Government’s decision to scrap the Royal Yacht. But it was Peter Shore who denounced it at the time.
Shore also supported Canadian against Spanish fishermen not least because Canada and the United Kingdom shared a Head of State.
Both on the Royal Yacht and on fisheries, even the Scottish National Party now agrees with him. For that matter, even Redwood, who was a Cabinet Minister under John Major, now agrees with him.