The following route fails hard at this line:

server.route({
    path: '/favicon.ico',
    method: 'GET',
    handler: {
        directory: {
            path: 'public'
        }
    }
});

The tutorial says it's allowed (and preferred over /favicon.{ext} — which of course does work).

I don't know enough yet but I think all routing rules ought to be deferred to hapi core.