Prince Charles, Prince of Wales seated next to the Queen's Imperial State Crown in the House of Lords Chamber, during the State Opening of Parliament. Photo / AP
There was no direct mention of her absence at the State Opening of Parliament but Her Majesty's presence was keenly felt.
The pomp and pageantry were there but the main event was missing, and Parliament and the public alike sensed it acutely.
Throughout her historic 70-year reign, the Queen's mantra has always been: "I need to be seen to be believed."
So it wasn't just a case of her absence being conspicuous but constitutionally significant.
The first time a sovereign has ever delegated their "Gracious Speech" to a member of the family, the unprecedented nature of the Prince of Wales standing in with the Duke of Cambridge was lost on no one.
In 1959 and 1963, a pregnant Queen relied on the age-old protocol of the Lord Chancellor doing the honours.
This was different. Although spun by aides on Tuesday as a "one off", by using a provision of the Regency Act to issue a new letters patent - rather than relying on royal convention - it appeared designed to give a glimpse of the royal future.
The defining moment was not so much the fact that she wasn't there but the notion that she may never carry out this most significant of royal engagements again.
To be clear, this was not the heralding of prince regency, the last of which was witnessed in 1811 when George, the eldest son of George III, was named Prince Regent when his father became too mentally unstable to rule.
This was evidenced by the fact that Prince Charles did not sit on the Throne of the Sovereign to deliver the speech but the inch-shorter consort's throne, and repeatedly referred to "Her Majesty's Government" throughout the ancient House of Lords ceremony.
The Imperial State Crown, meanwhile, remained unworn - its powerful presence in the Palace of Westminster signified by the raising of the Royal Standard over Victoria Tower.
While she may be experiencing what Buckingham Palace has described as "episodic mobility problems", the Queen remains in full command of her mental faculties and will maintain a busy diary this week, including a planned virtual Privy Council meeting and an audience with the Prime Minister by telephone on Wednesday. The 96-year-old monarch is also expected to undertake some private engagements later in the week.
That she instructed both Charles and Prince William to jointly exercise the royal function of opening the new session of Parliament was designed to send a clear message that "the boss" remains firmly in charge. They may have taken over duties such as the laying of the wreath at the Cenotaph, along with the carrying out of investitures and overseas royal tours, but it is HM and not her son or grandson who remains Head of the Armed Forces, Supreme Governor of the Church of England, Fount of Justice and Head of the Commonwealth.
As the longest-serving heir apparent in history Charles, 73, would not have wanted it any other way, having studiously avoided overshadowing his mother with any talk of his future reign.
Yet as he travelled down the Mall through Horse Guards and into Whitehall, at the start of what was a significantly scaled-down ceremony, there was no mistaking that some of the magic had been lost.
It perhaps did not help that unlike previous years, carriages were replaced with state cars, there was no Sovereign's Escort of the Household Cavalry and no Foot Guards street liners either - not to mention the fact that half the iconic Gothic building remains covered in scaffolding during restoration works.
Yes, the state trumpeters may have sounded a royal fanfare as the Prince of Wales arrived at the Sovereign's entrance with the Duchess of Cornwall, dressed elegantly in black and white.
But it felt a little like turning up at the opening night of a West End Show, only to discover that the lead part was being played by the understudy.
Although he looked dapper in his full Admiral of the Fleet uniform, with William, 39, appearing similarly well turned out in his morning coat, without the unique sparkle of the Queen, the procession betrayed such a lack of the femininity we have grown used to since 1952 that it felt like a formality.
Although it has been several years since she made use of the Robing Room to put on her ceremonial garb and Imperial State Crown, HM has always injected a welcome dose of colour into the procession down the 50-yard long Royal Gallery. This had the air of what Diana, the Princess of Wales, famously described as "the men in grey suits".
For decades we have grown used to the Queen's all-too-familiar high-pitched intonation punctuating the silence in the upper chamber.
While there was nothing wrong with Charles's delivery it lacked that characteristic monotone delivery that has long been emblematic of HM's resolute impartiality.
As one of four of the Queen's Counsellors of State, William's debut signifies yet another step in his journey to becoming the next Prince of Wales.
Although the first time he had attended, it was not all new to the father of three. He cannot fail to have recognised the 7th Marquess of Cholmondeley, who has been acting as the hereditary Lord Great Chamberlain since 1990 and thus was required to carry the crown on a red cushion.
David Cholmondeley and his wife Rose Hanbury, the Marchioness of Cholmondeley, who are based in Norfolk where the Cambridges spend most weekends at their country bolthole Anmer Hall, have long been in William and Kate's social circle.
Yet as he listened to his father deputising for his grandmother, William looked a little glum, channelling, perhaps, the sadness of a nation slowly coming to terms with the idea of transition.
For the palace, the focus remains firmly on next month's events to mark the Queen's Platinum Jubilee, with the public not only looking forward to celebrating HM's stalwart service but communities coming together again after coronavirus.
As she herself predicted at the beginning of lockdown, in that seminal speech: "We will be with our friends again; we will be with our families again; we will meet again."
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