Even as Henderson was happily accepting congratulations on behalf of the team who had revitalised Sprinter Sacre, another champion was getting stripped of his unbeaten record. "Oh my goodness, Faugheen's going to get beaten!" he exclaimed, catching sight of Punchestown on the big screen mid-interview. "…by Nichols Canyon," he added, with a gurn.
It's never politic to lower the colours of your own flagship hurdler with his stable companion but that's what trainer Willie Mullins did on Sunday. However, this wasn't caused by accident or misjudgment or design; it was the result of an improved horse, given his ideal ride, encountering a probably still-superior horse who appeared to be carrying some sort of problem.
It was an excellent ride from the young winning jockey, David Mullins, who was not permitted to claim his usual 3lb in a race of the stature of the Grade One Morgiana Hurdle. Nichols Canyon was at his best on the Flat when leading or given a relatively forward ride and that preference has extended to hurdling. His jumping, flawed especially when held up last season, has improved greatly. On Sunday, he really let fly at one or two hurdles, offering Faugheen no chink of light, and won in a good time.
Although Nichols Canyon could finish only a below-par third in the Neptune last season, pulling hard under a hold-up ride and making a critical error two out, he has progressed with every start since - winning at the Aintree and Punchestown Festivals in the spring even before ending Faugheen's unbeaten pomp here.
"That was completely different from the way they worked on Tuesday," said a bemused Mullins after the race. "Faugheen left him for dead on Tuesday and maybe he left his race behind him there. Who knows?"
It will be Mullins' job to find out. Jockey Ruby Walsh told the Punchestown stewards Faugheen had "hung right throughout". This was particularly evident when Walsh asked him to challenge Nichols Canyon from the second last and again after the last. To his credit, Faugheen tried to respond.
A visibly perplexed Walsh told Attheraces's Gary O'Brien on the day: "He just hung… It's not something he's done before… He just didn't pick up like he can." He was no more enlightened on Racing UK the following day and could only reaffirm that Faugheen's "zest" was absent.
Mullins will now also train Nichols Canyon for the Champion Hurdle, having shelved the idea that he's a stayer. Although he has something to find on the titleholder's best form, he's improving and merits being taken seriously - especially as his rivals played to Faugheen's tune in tactical terms at Cheltenham last March.
Mullins also saddled the Morgiana third, Wicklow Brave, who progressed into a Pattern-class stayer on the Flat this year. His start problems were not in evidence on Sunday and he was snapping at Faugheen's heels under a less and-the-kitchen-sink ride than the runner-up received. He, too, moves into the Champion Hurdle picture after here eclipsing his previous career-best when winning last season's County at the Festival.
If there is a threat to Mullins' ever-morphing stranglehold on this race, it may well lie with the 2015 Triumph Hurdle 1-2-3, all inmates at Henderson's yard, given the Supreme's principal players are all going chasing (at this stage).
Triumph winner Peace And Co and runner-up Top Notch are yet to re-emerge, but Hargam has returned with an at-best respectable fourth at Cheltenham last month.
Henderson also has an old favourite returning in My Tent Or Yours, now Geraghty's chief Champion Hurdle hope after it was announced in September that 2014 hero Jezki is out for the season. Hard-pulling My Tent Or Yours was only a neck behind Jezki on his banner day but missed last season with a tendon injury. The bar has been raised in this division since, however.
The other Mullins candidate (allowing there may be yet more being fashioned from the Carlow clay as I write), Arctic Fire, was progressive last season. This culminated in a nearest-at-the-line second to Faugheen in the Champion Hurdle and what probably should have been a defeat of Jezki in the Aintree Hurdle… until he fell heavily at the last. Faugheen then brushed him aside at Punchestown in May.
Arctic Fire has been out already this season, not needing to be in hailing distance of his best to account for Monksland at Navan earlier this month. The New One has won at Kempton as usual but has surely been exposed as not good enough. Irving has been busy, too, with a best-yet effort to take the Elite by seven lengths, having had a breathing operation during the summer. The top of the ladder is not within his sight yet.
His stablemate, Old Guard, the ready winner of Sunday's Greatwood Hurdle at Cheltenham off a mark of 145 (minus the highly promising Harry Cobden's 7lb claim), might yet end up contesting the Champion Hurdle according to trainer Paul Nicholls. Stepping-stones such as the International and Ladbroke Hurdles will start to establish whether he's good enough.