Depends on the asymmetry of how much it takes out of Roglic and McNulty. Surely Rogla will have to mark the attacks of Pogi by himself. And then - if the three of them are together on Arrate - I think 20'' are enough (depends on bonus seconds though).Yeah Pogacar can't win if everyone sits pretty until Arrate, and a very chaotic and hard race probably won't help McNulty.
In any case, we should have a good day of racing, even if we miss a great start of the stage.