Who has experience with different dancers as Odette/Odile?
When Natalia Makarova mounted her production of Swan Lake
for London Festival Ballet, some ballerinas did both roles while other casts were split. It allowed some beautiful lyrical dancers to perform the ballet even though they didn't have the technical wherewithal to do Odile. Likewise, some powerful technicians who weren't equipped with the long limbs and necks and pliant backs Odette requires were at least able to show off the brilliant quality of their dancing.
I've also seen the role split for dramatic purposes, as in John Neumeier's Illusions like Swan Lake
, in which the ballet is recast as the story of Ludwig II of Bavaria. (In producing a Swan Lake
with gay overtones, Neumeier preceded Matthew Bourne by almost 20 years.) Neumeier rechoreographs most of the ballet, but he keeps Ivanov's second act and the "Black Swan" pas de deux. In fact, Neumeier preserves an older version of Ivanov's choreography, complete with Odette's mime and huntsmen standing together with swan maidens during the "White Swan" pas de trois. In this version, the King attends a private performance of Swan Lake
, and, in accordance with Ludwig's swan fixation, becomes so enthralled by the story that he assumes the role of Siegfried himself. His fiancée, who has been completely unable to break through to him, sees this and is freaked out by it. However, during the next act she comes to his masquerade ball dressed as Odette, in a white tutu, and she and the King perform the "Black Swan" pas de deux.
Basically, my point was that the behaviour of Odette and Odile is so different, that I can't believe that Siegfried is duped into thinking that they're the same person. Some producers try to allay this by dressing Odile in white. I think the strongest argument in favour of some sort of enchantment is the Queen Mother, because otherwise it's difficult to believe she'd approve of her son's choice of such a crass fiancée. But fundamentally, I think the ballet is about the tension between chaste (I don't mean virginal) and carnal love, and this tension is lessened if Odette and Odile aren't two separate alternatives Siegfried must chose between.
Finally, I don't think that the fouettés are some sort of optional step that can just as easily be replaced by something else. A really spectacular set of fouettés can conquer an audience like few things can, so it's an expression of Odile's seductive power. When Siegfried stands roughly the same position and performs his own sequence of turns, it illustrates how completely he's been sucked into Odile's world. Besides, as Jack Anderson pointed out in "Idealists, Materialists and the Thirty-Two Fouettés," which I'm sure many of you have read, it's not just a step that's at issue. Replacing one step with another brings up the problem of what constitutes a given ballet.
Having said all that, I definitely prefer seeing one dancer in both roles. I am left in awe of ballerinas who can perform both parts well. Whether or not you think the role can be split at all depends on your reading of the story.