The horse himself — as his trainer, as mildly and modestly as possible, now feels compelled to argue — may conceivably be without precedent.
The separations of time, of course, ultimately make those of class impossible to measure.
It was not so long ago, after all, that the Turf was graced by other paragons in Sea The Stars, or Zarkava, never mind the giants of years gone by.
But if you take as your gauge the joy, emotion and theatre that suffused his latest epiphany here yesterday, then perhaps we have never seen the like of Frankel.
Before the Qipco Sussex Stakes, in which only four of them had a ride, the other jockeys poured out of the weighing room and squeezed through the crowds around the parade ring to glimpse the unbeaten favourite.
One veteran, a man who has seen it all before, stood next to a retired champion and discussed Tom Queally's options.
They watched the pale Irishman hoisted into the saddle by Sir Henry Cecil. “He just has to keep it simple,” they muttered.
Canford Cliffs, the big, dappled colt who ostensibly represented the biggest challenge yet to Frankel's immaculate record, looked relaxed and imposing.
But Frankel just took the breath away, brawny but fluid. His physique is increasingly pugilistic.
Though he was sweating up a little, his overall demeanour was so insouciant that it was easy to accept Cecil's theory that Frankel is outgrowing the reckless exuberance of his younger days.
Sure enough, he cantered to post with a coiled, easy rhythm — hailed, as he went, by cheers from the stands.
The three others had also been saluted with polite applause, unusual testimony to the tension pulsing through the crowd.
Then, at long last, the stalls were loaded. Judging from the breathless hush, they might have been the chambers of a gun.
For the first few seconds, Queally seemed menaced by the refusal of his rivals to set the pace. Not everyone, clearly, was convinced that Frankel had “grown up”.
As it turned out, however, they had played their one and only card. Once they saw Frankel relax in the lead, his pursuers surely knew the game was up.
After the hectic early charges of the 2,000 Guineas and Royal Ascot, this time Queally was conserving his mount's prodigious energy for the straight. Turning in, the two outsiders came off the bridle, and three furlongs out Frankel began to open up.
In the wake of his detonation, Canford Cliffs was left hanging abjectly towards the stands rail, punch-drunk.
Frankel won by five lengths, a margin unparalleled in four decades, but Queally could barely pull him up.
There was an immediate stampede to the winner's enclosure.
Amid prolonged cheers and tears, one gentleman in a panama called for three cheers for Sir Henry, and was heartily obliged.
Most knew of the vicissitudes Cecil had conquered to be here, both private and professional; and some, including owner Khaled Abdulla, will also have thought of Bobby Frankel.
The Saudi prince named his colt in memory of the great American trainer, who in 2009 lost his own battle with the same illness Cecil has been fighting.
The moment seemed saturated with the nostalgia of years to come, and Cecil sensed it demanded a corresponding perspective.
“He's the best horse I've ever seen,” he said. “I don't want to be facetious, and I'm probably wrong.
“I had a lot of respect for horses like Shergar, and Blushing Groom at his best. And I wouldn't know about before I was born. I can't go back to Tudor Minstrel, or to the days of match racing.”
He paused, and his reiteration was subtly strengthened.
“But I really do think he's probably the best you've ever seen.”
He almost seemed to be stressing that Frankel transcends the judgement even of a 10-times champion trainer, with 25 British Classics to his name.
“I wanted to have an envelope in my pocket, saying ‘five lengths or more',” he admitted. “But that would have been bad luck. I'm not surprised by how he won.”
Queally, whose intention had been to settle in behind, wore a relieved look after criticism of his aggressive tactics at Ascot.
Queally said: “He was amazing. I'm just very fortunate to be playing a small part in it. He's got that turbo — he's a freak.”
Frankel will be given a break and may well be seen only once more this year, in the Queen Elizabeth II Stakes at Ascot on October 15 — albeit the Prince indicated the Breeders' Cup might yet come under consideration.