A good corps de ballet makes a good company, and the Cuban Ballet Company - on tour in England recently - was no exception. Beautifully drilled and with a fine sense of timing and drama, the Cubans showed their worth in ''Swan Lake,'' ''Hamlet,'' and the second act of ''Giselle.''
The company's production of Tchaikovsky's ''Swan Lake,'' however, did not receive wholehearted endorsement from London audiences. One critic, David Dougall of the Sunday Times, called it ''the dullest I have seen.'' Indeed, there was some skepticism during the first week of the two-week stay in London about whether the choreography of the ballets chosen offered a clear view of the company's individual talents.
But the second week offered a triple bill that gave the company the reprieve it needed, and the Cubans left London for a week in Liverpool amid praise rather than disappointment.
The discipline shown on stage owes much to the strict selection of pupils in the company's ballet school at an early age - a pattern adopted from the Bolshoi and Kirov traditions in the Soviet Union. The Soviet influence is clear, and Soviet teachers have made regular visits.
The company expresses a Cuban national identity, too; it uses Cuban folklore and music in some of the repertoire. A film aired on British television just before its visit showed two dancers performing the Cuban folk tale ''The River and the Forest'' on a rigged-up platform to a large audience of factory workers at a Cuban steelworks.
Ideology is rarely absent: In the film, Alicia Alonso, a Cuban Ballet director and founder, who was a veteran prima ballerina who fled to the United States before Castro's revolution and was later invited back, thanked the hard-hatted workers for what they were doing ''for the revolution.''
To the dancers before the performance, however, she took a different approach , giving them a pep talk: ''Dance so people will never forget it,'' she said. The dance should give each member of the audience an artistic experience.
Here in London, two of the three ballets in the second-week triple bill included the corps de ballet, to great advantage. In ''Giselle,'' the troupe danced with such refinement and authority that their straight lines, expressive faces, unison in every step, and grace set an example that could benefit many other, more famous companies. The corps' Wilis were definitely girls who had been deceived in love and had died, ready now to take their revenge. Their cold, cruel manner when confronting first Hilarion the Gamekeeper and then Albrecht hid no remorse. Turning and pointing the way to the doomed, exhausted Hilarion, the corps moved like a long line of dominoes, the movement rippling front to back.
''Hamlet'' required the same unity and harsh approach to the story, but with a Cuban flavor. The corps, dressed completely in black and later in white, strutted around the spinning, brooding Hamlet, adding a touch of Spanish baroque to the mood. They danced to the sounds of rushing winds, air-raid sirens, and a theme that reminded one of the five-tone musical theme in the movie ''Close Encounters of the Third Kind.'' The dancers in the ''play within the play'' gave the only relief from the foreboding gloom and doom - a fiesta touch as they came on in startling orange rhumba-style costumes, complete with ruffled sleeves.
In an interview on the TV film shown here, company member Jorge Esquivel related how he was chosen from a children's home after the Cuban revolution to study ballet. Other men told of applying to be violinists or gymnasts but being carefully steered into ballet classes instead. Today there are two ballet companies in Cuba and 12 state ballet schools, and the company says firmly that ''there is work for all who graduate.''