I slightly regret not taking a decent 'before' picture of the blazer so that it would be easier to compare the effects of Child and Sons' changes. Suffice it to say that they have done an excellent job of adjusting the blazer to have slightly more narrowing at the waist, as I like it. For an off-the-rack garment, it now fits very nicely, and I am told by a friend that the combination of the small adjustments and the much nicer buttons makes it look like a far more expensive item than it actually was.
Unfortunately my camera is playing up so I've had to take a webcam photo - without very good results. In any case, I think the project was a great success, and, as the weather gets nicer, I look forward to wearing the blazer more often. Perhaps Bertie Wooster style, with some white trousers.
But probably not the captains cap.