HBO chairman-CEO Michael Fuchs isn’t sure what direction the predicted 500-channel universe will take, but he see its advent as less of a threat to the pay service than the explosion of VCR ownership that occurred during the 1980s.Speaking at the TV critics tour, the HBO exec also expressed skepticism about the hubbub over violence on television and forecast hard times for the broadcast webs, saying he sees “nothing very positive for the traditional commercial networks” in the future. Asked about whether “The Larry Sanders Show’s” Garry Shandling might still fly the coop for a life-imitates-art network talkshow, Fuchs said HBO will “continue with Garry’s show as long as he wants to do the show.” Shandling was noncommittal about any talks with CBS during a session plugging his show later in the day, while CBS Entertainment prez Jeff Sagansky said Saturday that Shandling was on the web’s “short list” for the 12:30 a.m. slot but that the main priority now involves successfully launching David Letterman’s talkshow. In regard to programming, HBO said Billy Crystal, Whoopi Goldberg and Robin Williams will again host “Comic Relief VI,” to air Jan. 15 and originate from Los Angeles. HBO also said it’s reaffirming its commitment to documentaries, with four specials to air from September through December. They are “Paha Sapa: The Struggle for the Black Hills,”"By Satan Possessed: The Search for the Devil, “”Detective of Death: Confessions of a Medical Examiner” and an “America Undercover” docu set in a Philadelphia inner-city school. Another “Undercover” documentary, “Why Am I Gay? Stories of Coming Out in America,” will air Aug. 10, exploring personal stories and the issue of whether there’s a genetic factor predisposing people to homosexuality.