Just when one might have thought the Theater of the Absurd was but a distant memory of endless evenings in bare, darkened lofts, the curtain has gone up on the sideshows of the Gorbachev-Reagan summit.

Absurd is the word, for who, 10 or 15 years ago, would have dreamed up yesterday's scene in the packed ballroom of the National Press Club? Consider it:

Jewish activist Natan Shcharansky, freed in February of last year after nine years in a Soviet labor camp, visiting from his home in Jerusalem, smiling quizzically as Soviet editors and officials answered questions from a frequently garrulous Western press corps on Afghanistan, Stalin's purges and the Soviet criminal code, all of it in the name of an old word from the days of Peter the Great -- glasnost. Who would have imagined it?

Shcharansky sat quietly in the audience of 200 journalists and spectators. "This is my first glasnost-era briefing," he said. "Of course, I was briefed many times myself in Russia."

Just then a slightly inflamed questioner rose from his seat and tossed the first incendiary device.

Between 1936 and 1939, he barked, Stalin sent millions to the gulag and hundreds of thousands died. What is in Soviet law to prevent that happening again? And so on, until he sat down.

The translators and four high-ranking Soviet officials and editors began nodding and looking at each other as if to say, "Well, tovarishchi, who's on deck?"

Shcharansky leaned forward, looking a bit nervous and out of sorts. What was this?

Perhaps the questioner thought what he had asked was shocking or in some way extraordinary. And no doubt some were expecting an answer from the dais at least as sharp as the question itself.

Instead, the response from Communist Party spokesman Albert Vlasov was patient, breezy and cool -- if unconvincing to his questioner.

"What happened during the time of the cult of Stalin, we write about it and talk about it openly. There were difficult moments in our history and glorious moments, and we talk about them openly. You see . . ."

Shcharansky frowned. He could not "see" at all.

Next, someone directed a question at Vitaly Korotich, the editor of Ogonyok magazine, and Yegor Yakovlev, editor of the Moscow News -- both leading figures in Soviet journalism and known for publishing some controversial material. Why, the reporter asked, have they not tried to publish the Oct. 21 speech of Boris Yeltsin -- the angry speech at a closed party plenum that led to the former Moscow party chief's firing and denunciation.

"Well," said Yakovlev, "I have to say I haven't tried and would have thought it incorrect to publish a speech at the party plenum. One reason was, there were 26 or 27 speeches at that meeting and I'd have to publish all of them."

Shcharansky giggled at that. Yakovlev went on.

"You can't give me an example in the last decade when the speeches at the party plenum were published. Maybe in due course we'll have different ways, but now . . ."

Someone belted out, "When are you going to have a free press?"

"I believe we do have a free press," Yakovlev said.

Korotich, who has led several town meetings in Moscow, tried to seize and calm the moment. "I have to say the speech by Yeltsin was made under certain circumstances. The thing is, a plenary session is an internal party affair and journalists are not allowed there. Questions of an internal nature are discussed openly, but it's within the Central Committee."

Shcharansky had had enough.

"I must tell you it's a very strange feeling to listen to this," he said at the door. Shcharansky has spent his time in Israel and America appealing to Western leaders to pressure Gorbachev to open Soviet borders, and like many e'migre's his view of glasnost is deeply (if understandably) cynical.

"I had the feeling I was at the headquarters of the KGB again. You see, at the lower levels, the KGB is rude and tough, but at the top they are rather intellectual and smooth. The way they answer questions now is a lot like that. They acknowledge almost every problem in the distant past, but they really won't confront problems that are still going on now.

"Glasnost is not a form of freedom. It's just a new set of instructions on what is and isn't permitted."

Throughout the briefing, the questions seemed more like taunts than queries: When are you going to allow freedom of religion? When are you going to have open elections? Several questioners seemed genuinely miffed that the Soviets did not throw up their hands and say, "Well, you're right, you've got us there!"

The answers were often at least as frustrating as the questions. Asked why the Soviet system allows only the Communist Party in the political process, Vlasov said the one-party system "satisfies the people."

Occasionally there was an informative moment. Since the Yeltsin affair there has been much speculation that conservatives in the Soviet leadership will begin to limit glasnost, forcing such publications as the Moscow News and Ogonyok to stop printing critical and investigative articles.

"There are conservative forces in Moscow that oppose glasnost," said Korotich, editor of Ogonyok. "But at the same time there are many people who stand strongly for glasnost and that number is increasing."

Korotich denied that he and other leading figures of glasnost were feeling pushed since the Yeltsin affair to stop operating as they have this past year or so.

"I don't feel any pressure on me from the leadership of the state," he said. "Recently we published an interview with the widow of {Nikolai} Bukharin {a revolutionary leader who was executed on trumped-up charges during Stalin's purges}. There was speculation in the Western press on how this would affect the future of the state, and printing the piece was regarded somehow as a directive from above. I give my word of honor that we ourselves sought the interview and the leadership read it only after we published it in our magazine."

But more often the answers were fascinating only for their style. By way of denying that the Soviet Union has violated the 1975 Helsinki Final Act, Vlasov sewed an elaborate metaphor: "You have a suit on and I have a suit on. Your suit wouldn't suit me and my suit wouldn't suit you. We shouldn't try to switch suits and . . ."

And on it went. The level of performance was usually higher than the level of discourse. Spectators asked "hard-hitting" questions and the Soviets were "open."

"It shows that in terms of dealing with the American media, the Soviets have gotten out of kindergarten and they've moved up to, oh, around the seventh grade or so," said Jonathan Sanders, a Columbia University Soviet and media specialist who was sitting in the audience.

"Look, they're answering all the questions, the translations are good, no one's walking out in a big huff, even when the questions are ridiculous. Of course, they're answering some of the questions with a lot of baloney, but that's to be expected."

Sanders sighed. "It's fun to watch, though, isn't it?" he said. "History marches on."