Yeah I can see your point, but if they are the best it shouldn't matter is my thought. Okay they have been preparing for a particular fighter and when that changes it would be frustrating, but their new oppone t would be at no advantage either...so if you truly are the best then prove it!
This is why Conor's mentality is so good. Kavanagh said that he never prepares specifically for a fighter, that every day is simply focussed on himself being better than he was yesterday...which is why Conor states that the opponent does not matter, they are all the same because he is ready for all. Gotta respect that.