Clearly, success or failure doesn't only hinge on proportion and timing and narrative shaping. It's about performing talent, and the Royal Ballet's is currently riding sky- high. A production should also be flexible enough to let individual dancers make their mark, and though Tamara Rojo and Carlos Acosta have been paired in Giselle before, there's never any knowing where they will take it next.
Rojo is, above all else, an actor-dancer. From her first appearance at her cottage door she physically marks herself out for tragedy. True, we've just watched the glossy-smooth Acosta prepare the way for her seduction - ditching the ducal cloak and sword to pose as a local - so we're primed. But there is something unbearably tender about the dip of Rojo's head, the squarish set of her body and the blithe skip in her step that makes us want to leap up there and protect this child from harm. Rojo pushes the social issue too: her Giselle is the poppet who gets to present the posy when local toffs drop by, and that cringing humility - inscribed in every muscle - is in turn almost cringe-making in the way it beckons to tragedy.
While Albrecht is often played as a straightforward cad, Acosta's reading is more complex. Yes, he's a deceiver, yet part of him is sincere. It's not just embarrassment that racks him when his scam is revealed, it's panic that he'll lose his precious love. Yet when Giselle runs to his arms in her frenzied last moments, his split-second response is to raise his hands to protect himself. In short, he's a man in a mess.
Further telling details inform Act II, when death, and Giselle's incarnation as an airy spirit, ironically unite the pair in defiance of the terrifying Wilis. I loved the trance-like rallentando of Acosta's repeated grabs at Rojo's vanishing form, as if trying to embrace a patch of fog. She, for her part, really does appear physically transmuted, as well as sadder and wiser all round. The package is wrapped in ensemble dancing of outstanding discipline by the corps, united in their lust for vengeance yet chillingly serene - a superb company effort.
Another solid piece of work elevated by exceptional performances - in this case of The Sleeping Beauty - leaves English National Ballet more of a force to be reckoned with as it adjusts to its new director, Wayne Eagling. This Beauty was commissioned from Kenneth MacMillan by American Ballet Theatre, but it's based on the same Russian text he learnt at the Royal. So, no surprises then: the story is succinctly and fluently told, the familiar steps are all there, and aside from the symphony in ruched peach that makes the Garland Dance resemble a 1980s window treatment, costumes and sets are refinedly gorgeous.
But all of that paled on Wednesday night under the blistering radiance of Agnes Oaks's Aurora. Petipa's writing in this ballet allows little scope for dramatic naturalism. Yet Oaks mines the narrowest seams of possibility within the steps to create a compelling picture of the three ages of woman - from bubbly girlhood to seductive muse to gracious maturity in the course of three acts. Given the stylistically immaculate match of Oaks with real-life partner Thomas Edur, it would be nice to report that his impact was on a par. In truth, still recuperating after injury, this Prince was pacing himself rather carefully. Nonetheless, the pair's exultant final duet, complete with blink-and-you'll-miss-them fishdives, left the Coliseum on a roaring high.
'Giselle', Royal Opera House, Covent Garden, London WC2 (020 7304 4000) continues in rep until 11 February