You'd be thinking of Jimmy McGregor, better known as a singer/musician, but I couln't dig up anything meaningful about his time on TV, just that he made appearances.
I agree that far too many programme makers are driven by the analysis of the audience, and lose sight of the aim and target audience their programme should be intended for, and concentrate too much on targeting the 'top percentiles'. A case of wanting a small slice of a large cake, rather than a large slice of a smaller cake. There are many programmes now, particularly on the BBC, where they are painfully evident as having been assembled to a formula, rather by anyone with a heart, or some passion for their work.
All is not lost however, and 'Iomall nan Tonn' or 'The Edge of the Waves' which was shown on ITV, and contains some truly superb aerial camera-work of Scotland, is a welcome exception to the rule.
One's boredom is another's passion.