Oberon in Frederick Ashton’s The Dream was the hurdle at which the ferociously promising young Sergei Polunin refused when he quit the Royal Ballet last week, and whether it was the deceptive complexity and difficulty of it that caused his sudden exit, last night’s opening gave his replacement, the brilliant Steven McRae, such a run for his money that it wouldn’t be surprising if the role had indeed left Polunin in a blue funk.

Sergei Polunin’s flight this week from the Royal Ballet just as he rises to the pinnacle made last night's Sadler's Wells show a very hot ticket for those who wanted to catch his guest appearance in it. But the evening was also a proclamation that this isn’t the first time that company has mislaid one of its finer talents.

The young Royal Ballet star Sergei Polunin, Covent Garden's most remarkable male discovery for years, has quit the company in a stunning shock that today sent consternation throughout the ballet world from the USA to Japan. But tonight Royal Opera House chief executive Lord Hall said that he believed the company should support the dancer in "thinking about his life - the pressures on him are enormous", indicating that Polunin was undergoing a crisis and the door to his company remains open.

A few years ago, the word was that a new choreographer was showing interesting things. His name was Liam Scarlett, and although he was very young, some work that had been seen in a workshop was looking promising. It was not long before “promising” became actuality, and Scarlett’s first piece, Asphodel Meadows (main picture), was premiered on the Opera House stage.

Highlights of the year are always interesting. Things you loved at the time do, sometimes surprisingly, fade very quickly. I really enjoyed the Gabriel Orozco retrospective at the Tate: I thought it inventive and exciting. But now I have hardly any memory of it, and can no longer visualise what enthused me. (Well, apart from the sweet photos of two scooters flirting with each other. But that’s really not enough.)

The year’s best arts story was not the cuts (which isn’t art, it’s politics), but the appearance in Edinburgh of a mysterious series of 10 magical little paper sculptures, smuggled into the city’s libraries by a booklover. No name, no Simon Cowell contract - it proved the innocent gloriousness of the human impulse to make art, a joy that has no expectation of reward but without which no existence is possible.

No more is dance the preserve of the few sitting in the theatre - larger companies are leaping hungrily for TV and now cinema screens, having found various ways around the longstanding obstacle of copyright. The BBC is experimenting with live 3D cinema for Saturday's Strictly Come Dancing final, the Royal Ballet is beaming Thursday's performance of The Sleeping Beauty live to the world's cinemas.

The Nutcracker, if this isn’t too much of a mixed culinary metaphor, divides audiences like Marmite: love it or hate it. Usually it’s the critics who hate it, and for them it is often only the annual round of Nuts to be Cracked that wears on the soul. It is hard to imagine, otherwise, that anyone with functioning ears can fail to be thrilled as what is arguably Tchaikovsky’s greatest orchestral work begins to swell from the pit.

“Over the top” is a curious expression. Originating in World War One, to mean going over the edge of a trench and into battle, it has altered by degrees to mean anything extravagant or outrageous. And Gloria, which is arguably Kenneth MacMillan’s masterpiece, has both the literal and figurative meanings of going over the top layered upon each other.

On Saturday one of the master ballets of the Royal Ballet genius Frederick Ashton returns to the Covent Garden stage, Enigma Variations. Its owner is an architect, one of Ashton’s last friends, and one of the handful to whom the choreographer left the small number of ballets he felt would be of financial benefit to them when he died in 1988. But as time goes by, those ballets' ownership passes on to others, and worries have been mounting about their vulnerability in an art form written in ephemerality.