Actually playing a back 3 is completely different and not many clubs actually use it so why would we when we are set up as a back 4 and quite competent at it. In a 3 your wide CBs need to be able to go out wide because of the absence of a fullback which I would say Brown could do but Moore couldn’t. And obviously the most important positions in it are your wingbacks, of course Leigh could play that role although DB clearly doesn’t trust him for an important role so why would he start now and also who would do it on the right, Kioso and Ter Avest are full backs aren’t they. I suppose they could shoehorn a midfielder in to do it but that’s another player out of position. Just my humble opinion to all the armchair coaches on this forum.