Hauntingly and prophetically, Tom Daley the other day estimated how long it takes to know the difference between flying with the eagles and making a pancake landing. It is 1.6 seconds and then you slam into the water, at 34mph.
This is not much time in which to crowd four years of déjà vu but when yesterday he walked into the late afternoon sunshine without the gold medal – or one of any kind – which had beckoned so brightly less than an hour earlier, you knew that he had travelled all the harrowing way back to Beijing.
He had a few more guards against the despair that engulfed him as a 14-year-old battling the pressure of his first Olympics, and no doubt it helped that another, much older partner in the synchronised 10m platform event this time took on the burden of blame.
But there was no hiding from the pain that came at the end of one of the toughest years of his brief but hugely celebrated life. It is that particularly harsh torment which you know is going to accompany you for quite a sizeable slice of your life. It's the one wrapped around the possibility you have missed the greatest opportunity that would ever come your way.
That certainly seemed to be in the air when Daley and Waterfield reached the halfway point of three brilliant dives in the gold medal position, nearly two points clear of the Chinese favourites Yuan Cao and Yanguan Zhang. But as the former infant prodigy kept hammering home these last few days, the moment you speculate on the future while taking your eye off the moment you already have one foot in disaster.
Waterfield, whose success in Athens was watched by the 10-year-old Daley from a Cornwall caravan site, was quick enough to take the blame, saying: "I kicked my heels up too high on the fourth dive – and then I said: 'Sorry, mate'."
At the end, when they had slipped to fourth place, behind the refrigerated Chinese, the marvellously aggressive Mexicans, German Sanchez Sanchez and Garcia Navarro, and the Americans Nick McCrory and David Boudia, the British pair gave each other a small, sad hug – and Daley said: "We win as a team – and we lose as a team."
These were sentiments which may have come from behind gritted, immaculately polished teeth but they certainly were a lot easier on the mind than the aftermath of the last place Daley shared with Blake Aldridge in the Beijing Water Cube. That had all the soothing properties of the drive off the cliff edge in the last reel of Thelma & Louise.
Aldridge savaged the kid, calling him "Thomas" and saying that he had contributed to the loss of the medal he had fought for throughout his career. The boy had cracked under pressure, suffered a panic attack. Quite reasonably, the 14-year-old had certainly complained when his senior colleague decided to call his mother on his mobile phone in mid-competition.
Mother, it turned out, didn't know best on that occasion and the partnership broke up as quickly as you might imagine.
Coming into yesterday's final Daley spoke of the loss of his father to cancer. He said that the sadness would be somewhere at the back of his head as he strived to fulfil the family dream, but he also told of the endless battle to find a mature focus on the only thing that mattered at the Olympics, which is that pure concentration required for that last millisecond of each of six dives.
As Waterfield lost his fourth dive, a series of somersaults placed in the high-scoring most difficult category, a rush of disbelief reached every corner of the Aquatics Centre except the one occupied by flag-waving Chinese. They knew, in that razored second, that the threat of Daley and Waterfield had been swept away.
For Daley the obligation, as he headed away from the glare of the Olympics to the team's training camp in Southend, was to store away another set of raw emotions and clear his head for the individual battle against China's No 1 diver, the imperious 19-year-old Qui Bo.
Bo hasn't been beaten for two years but Daley does have one early victory against him. He also has the theory that if the Chinese are brilliant – and certainly we had more evidence of that yesterday from Cao and Zhang – they also tend to the robotic. That works well enough, he suggests, until the pressure becomes insurmountable. "In diving," added Daley, "you just never know for sure what's going to happen next."
Yesterday there was no argument about the general proposition – only the identity of the most likely victims. For a little while Tom Daley's long days of ultimate promise, the lionisation of a boy with a jaunty smile and a fine level of talent, seemed to be on the point of a glorious fulfilment.
He had gold at his fingertips – and the first one for Britain. It was a bewitching prospect right up to the moment Waterfield, the hero of his boyhood, raised his heels fractionally too high.
One consequence was that Daley last night received a tweet suggesting he had let down his beloved father. This left one last hope on a day of some bruising to the spirit. It was that Daley managed to reject such poison in the shortest period of time – maybe as little as 1.6 seconds.