Years ago, I read about a classical guitarist (named Narciso Yepes, although I had to look his name up; I didn’t remember it) who commissioned the building of several guitars with extra strings, including a ten-string guitar, and asked his friends which one sounded the best. They voted for the ten-string.
Be that as it may, note that the anecdote implies that he became at least competent on each of the guitars. I wonder how many configurations Keith Medley went through before deciding that twenty-seven strings was the correct number to get the sound he wanted?