Fantasyfan beat me to that quote! Coincidentally, I've been working my way slowly through the entire Doyle œuvre about Holmes and I find I don't really like it and for just the reasons this quote implies. They're too carefully structured to admit of only one possibility and it all seems so silly and artificial to me. These frothy and antic stories hold a lot more appeal. Although if I had been Rupert or Swinburne, I'd have been tempted to knock Basil's block off if he had laughed at me one more time, offering no explanation for what was going on.
Reading Chesterton, I always wonder about the religious undercurrents, but I'm not sure there are any, or at least any fully-formed, here - an early work, of course. And yet there seem to be elements of the Holy Fool about Basil and I thought
this article seemed apropos. The Holy Fool is more an orthodox notion than western, but Basil of course is an eastern saint and St. John Chrysostom also gets a mention.