Those dancing feet - two ways to view a musical

Between those knock-'em-dead-baby dance numbers in ''42nd Street,'' a character, thrilled to his tingly toes, turns to the audience and cries out: ''Musical comedy! The two most glorious words in the English language!''

Well, the Man in Row K wouldn't go that far. But he'd go a whole lot further than he would have a few years ago.

As he sat there and listened, with no visible resistance, to ''Shuffle Off to Buffalo,'' he could hardly believe what had become of him. Once the Man in Row K had belonged to the school of serious - and we do mean serious - theatergoers who want the stage reserved for Aeschylus and Shakespeare and Ibsen. Samuel Beckett, at the very lightest. Our man's prejudice against musical comedy was just about the firmest thing about him.

The fussing and fretting began with the music. To the petulant ear of the Man in Row K, pit orchestras were the pits. All those indecently frisky violins! All those not-quite-syncopating saxophones! All those awfully razzamatazz trombones, leading up to another heavy rim-shot from the drummer! Everything was so incorrigibly peppy - except, of course, the love songs. Pure saccharine syrup.

The problem was, the Man in Row K loved jazz. He gave passing marks to ''Porgy and Bess.'' Against his better judgment, he liked Cole Porter. But everybody else was put down as Tin Pan Alley, with accent on the Tin. Broadway could not be forgiven for failing to enlist Duke Ellington often enough - the short-lived ''Beggar's Holiday'' was the best musical he ever saw, the Man in Row K always maintained.

The only good thing the Man in Row K could say for most musical comedy scores was that most musical comedy books were even worse. Underneath the song and dance, the earthshaking issue was always the same: Will Boy get Girl? Some cliffhanger!

When musicals became more sophisticated, the Man in Row K refused to be impressed. He called ''The King and I'' and ''Camelot'' the ''royal floats.'' He referred to ''West Side Story'' as ''neon-contemporary.''

If you got the Man in Row K started - or even if you didn't - he could preach a whole sermon against the musical comedy.

Musical comedy was noise and hype and flashy costumes - a whirlwind going nowhere.

Musical comedy was aimless American energy and mindless American good cheer at their national worst.

Musical comedy was Vanity Fair.

Whatever happened to that growling old spoilsport who sneered through ''The Sound of Music'' and snored through just about everything else? Here he was, in Row K, going moist-eyed over ''The Lullaby of Broadway'' - allowing a chorus of tap-dancers to pulverize his iron opposition into tapioca pudding.

''Why, oh why, oh wherefore?'' - to quote the showstopper from ''Hit the Deck.'' The opinions of the Man in Row K hadn't really changed - just his expectations. He was no longer waiting for the perfect party, where all the dialogue was by Oscar Wilde, and all the food by Julia Child, with Andres Segovia strumming in the background. His new rule was: The urge to celebrate is more important than the style in which the celebrating gets done. If somebody wished to toss a hat in the air, the Man in Row K was through criticizing (a) the hat, (b) the toss, or (c) the catch when the hat came fluttering down. Somebody else would have to pick these nits.

On the other hand, when he stumbled out of Row K and made it back home, he was certainly going to play some Duke Ellington records, sort of to rinse out the old palate. But no offense to ''42nd Street.'' And just to prove it, he'd start with ''In a Mellow Tone.''