THE LITTLE ELEPHANT IS DEAD - Through Saturday at the Kennedy Center's Terrace Theater.

It's a plot. Roger Stevens, having been criticized for filling the Kennedy Center with a theatrical taste that runs to Deborah Kerr and lots of costume changes, is putting "avant-garde" with a vengence in the small upstairs Terrace Theater. Is it a trick to make everyone who has asked for more daring or intellectual theater rush back into Deborah Kerr's arms and sob repentantly on her chiffon bosom?

The current offering is "The Little Elephant Is Dead," a one-hour Japanese play by Kobo Abe in which the actors spend most of their time under a huge sheet, apparently having pillow fights. When they come out, they dance under a strobe light or eat apples. Also, they project pictures of fish on the wall and English subtitles to the Japanese dialogue on one another's costumes.

This is actually apres-garde theater. The inexplicable, frightening, illogical, neurotic dream reflecting the chaotic violence of the modern world, etc., has been the mainstay of "experimental" theater for several decades, and of modern dance for decades before that.

It has occasionally been done well, certainly better than here. Compare any Samuel Beckett dialogue with quintessential Kobo Abe: "The main thing is the feet, and I have no feet." "Is it only feet you don't have?" "I have no ears, no neck, no shoulders." "And, above all else, you have no arms." "I want to touch! Let me touch! A world I cannot touch might as well not be there!" "Pseudo-fish." "Pseudo-fish." Some acrobatics in this play are good, but any decent dance troupe expresses the body better to express the tortured soul.

But is has become a bore to see it done at all. The "experiment" produced mixed results, but need not be repeated.

Deborah Kerr's interests aside, one wonders whether black and abstract theater are being judged by lower standards, a form of patronizing they do not need. They is certainly first-rate black theater to be found, and an avant-garde theater that happens to be marching toward new ways of expressing human problems other than "alienation."

And in this case there may also be an equally degrading "mysterious East" factor, in which it is assumed that there must be something deep there - by those who are unaware that Japanese theater has for centuries excelled in poetic clarity. CAPTION: Picture, A SCENE FROM "THE LITTLE ELEPHANT IS DEAD."