It was, at times, more than respectably good, but it was never the "Swan Lake" it should have been. American Ballet Theater gave its first performance during its current visit of the Petipa-Ivanov-Tchaikovsky classic Thursday night, with Martine van Hamel and Clark Tippet as the leads.

When, toward the end of the final act, the evil magician's castle failed to collapse on schedule, and instead had to be ignominiously reassembled, it seemed unintentionally symbolic. This was an evening of almost-but-not-quite.

The casting had raised expectations to unusual heights. Van Hamel has not only established herself as a remarkable tragedienne and classical stylist; she has also shown herself, in previous performances, to be capable of a depth and poignancy in the dual role of Odette-Odile that few other dancers of the current era can match. Tippet, too, though he is still a relative newcomer to the part of Siegfried, has been making splendid strides as a dancer, and particularly in his partnership with van Hamel.

Dance, however, is an evanescent art in every sense. Some nights everything clicks, some nights nothing does, often for reasons no one can clearly pinpoint or explain. This "Swan Lake" was by no means a dead loss, but it looked more like a mechanical runthrough than a galvanized performance.

It wasn't a matter of faulty execution. Most of van Hamel's dancing was a model of refinement, though she had some troubles with the Black Swan bravura. Tippet was actually stronger in the role technically, in the few bits of dancing Siegfried is allotted, than we've seen him before.

But as an artistic experience, "Swan Lake" doesn't stand or fall on its pyrotechnics. The trouble was, neither of the principals, and scarcely anybody else, for that matter, seemed to have their heart in it.

I say "seemed," because what a performer feels and what he or she projects are on no account always identical. What came across the footlights on this occasion, however, had but dim dramatic impact. Van Hamel's Odette seemed too abstracted; her Odile edgy. Tippet looked too posed to be a convincing prince or lover. Knowing the artistic mettle both possess, one can safely dismiss this evening as an off-night.