Behind any Royal wedding pulses — among its hordes of fretful planners — is the atavistic fear that the bride will be upstaged by someone.
Maybe it'll be a precocious pageboy. Or perhaps a bridesmaid's shapely derriere.
It's a funny old wedding, however, in which the bride is upstaged by the clergy.
And yet that is exactly what happened.
It began as a largely routine Royal wedding, remarkable only for the extra wattage in its star turnout.
The weather was perfect, the crowds gathered and the Queen disembarked from her Rolls Royce dressed in a shade that no other nonagenarian in the world would be self-possessed enough to attempt.
The invited guests took their seats with that slightly entitled air common among people who have had to be instructed on the invitations to wear hats but not swords please.
The published order of proceedings (which still included the bride's father, a moment of thrift having precluded the printing of a fresh set) was at once over-detailed and somehow dull, like the persistent whisperings of an extremely reliable equerry.
At 11.45am the Mother of the Bride, Ms Doria Ragland, arrives at the Galilee Porch and is received by the Dean of Windsor and is conducted to her seat in the Quire.
At 11.52am Her Majesty The Queen arrives at the Galilee Porch and is received by the Dean of Windsor who presents the Canons of Windsor and the Archbishop of Canterbury.
Those in the Quire stand as Her Majesty is conducted to her place in the Quire. A fanfare will sound.
And then the Reverend Michael Curry spoke.
From the outset, it was clear that this was not going to be a standard Church of England sermon, which tradition dictates should be delivered in the tone of a very shy person asking the way to the train station.
A copy of Reverend Curry's address was distributed in advance, but he immediately went off script, barely glancing at the tablet in front of him on which his prepared words blinked patiently.
He started with the Reverend Martin Luther King, then into an energetic reverie about love.
"Now the power of love is demonstrated by the fact that we are all here," he enthused, hands flying.
"Two young people fell in love, and we all showed up. But it's not just for and about a young couple who we rejoice with. It's more than that."
At this point, guests began to exchange glances.
Princess Beatrice (fresh from disappointing the gathered crowds by failing to wear a hat that looked as if she were attempting to establish contact with a distant galaxy) assumed an expression of goggle-eyed amusement.
"I am talking about some power. Real power," the visiting churchman continued, his delivery building to a rhetorical peak, prepared text receding in the speech's rear-vision mirror.
"Power to change the world! If you don't believe me, well, there were some old slaves in America's Antebellum South who explained the dynamic power of love, and why it has the power to transform.
"They explained it this way. They sang a spiritual, even in the midst of their captivity. It's the one that says there is a balm in Gilead — a healing balm."
Elton John, in his pink plastic glasses, frowned in puzzlement as the guest in front of him stifled a smile.
The Queen was seen to shrug slightly in resignation. Prince Charles looked exceedingly awkward. Zara Tindall gave a long glance of disbelief that was later described as "side-eye".
Martin Luther King! Slaves! Now, England didn't have an elaborate formalised slave-owning racket the way America did, but one could very confidently say that among the 600 assembled there would be plenty whose vast inherited fortunes were boosted at some point by the blood, sweat and tears of fellow humans who were not paid for their trouble.
So the Reverend's words were … bold. And loud. And fuelled by a passion and showmanship that — while by Episcopalian standards the preacher was barely tapping his foot on the accelerator — made many of the Royal guests either look at their shoes or giggle.
He mentioned "love" 58 times; this might explain the discomfiture of Prince Charles, who at the time of his first marriage expressed some difficulty with the concept.
But there was one woman who looked entirely comfortable, nodding along contentedly to the words of the visiting bishop.
And it was the woman who otherwise had the most reason to feel ill at ease — the woman who only two days earlier had flown from California to London to meet the Queen, say hello to her only daughter, then head to a castle built one millennium ago by William the Conqueror to see that daughter marry a prince in front of a global television audience of 20 million or so.
Doria Ragland — whose own ancestors were slaves, and who was unaccompanied at the ceremony, quietly wiping tears from her cheeks as she watched her daughter — was quite at ease with the soaring rhetoric, and didn't seem to notice the bubble of nervous hysteria building among the congregation.
Never was the difference between two cultures more apparent.