You can't base KRG on a line through one horse. Lord Byron was in great form at the end of last season and is clearly not in the same place currently.
What is fact is that KRG followed up his win in the Turners by winning another grade 1. The 2nd hasn't raced but the third won a grade 1 whilst the 6th beat the 4th in another grade 1 (Lord Byron was 4th beaten 6 1/2 lengths suggesting either Lord Byron continued to improve or that KRG was below par still at Punchestown). We haven't seen the 5th out either. That form couldn't look any stronger in the novice division. Whether they train on and where they go will remain to be seen but as of the end of last season it looks very good.
As to how good those middle distance novices were, we shall see in time. My assumption was that the 4yos were decent and it tied in nicely with the form. The only real link we have was through the 2m novice at the DRF where Talk The Talk then disappointed in the Supreme. However, Ballyfad disappointed in the Turners also, though he bounced back with his 3rd at Aintree behind Bossman Jack and Soldier Reeve. Maybe the best argument for you is through Koktail Brut, who was beaten 6 1/2 lengths at Leopardstown, but then was only a 13 1/2 length 8th in the Supreme, despite a higher RPR and then followed up in a grade 2 at Fairyhouse over 2 miles (Was probably over the top by his last run at Punchestown). Personally, my instinct was the Supreme was suspect. Three British horses involved in a tight finish doesn't scream it is form that is strong and will stand up. I could well be wrong though. The Irish challenge in the race wasn't that strong, El Cairos and Mighty Park lacked experience whilst Talk The Talk was a drifter on the day in the betting. Our best guide will be seeing how Mydaddypaddy and Idaho Sun get on over hurdles in open company.