I've been the biggest preacher of 5yo trends in this race for years, but I've been swaying towards consideration that it's less the 5yo issue and more the Triumph hurdle factor.
The New course being a much bigger test of stamina stretched a 4yo stamina to the limits, therefore switching back to the speedier Old course a year later is a tough ask, and sadly we see very few 4yo in the Supreme, also run on the Old course (despite the weight for age allowance), so this theory can't be fully tested.
But all that said, I thought very early last year that DDS could be a very special horse and still believe that, I think the odds are stacked against him but if he was to succeed it would be some feat.
Worth remembering also that throughout last year connections thought Charlie Parcs would be their leading Triumph horse, I think it was trials day and they were both declared, all the money was for CP until he was pulled half an hour from the race.