There were times during the Oldies Show at Wolf Trap last night when the evening's theme--"rock 'n' roll is here to stay!"--seemed more of a threat than a boast.

The concert began with the Bobby Comstock Band draining every ounce of personality from a number of rock classics. The band then spent the evening providing support for the show's headliners--Bo Diddley, The Crystals and Little Anthony.

Like a prizefighter well past his prime, Diddley has lost much of his punch. His show is now steeped in self parody, gimmicks and sluggish vamps. Only the still-hypnotic "Hey Bo Diddley" managed to suggest his true place in rock 'n' roll.

The Crystals fared much better. The trio brought to life such hits as "He's a Rebel" and "Da Doo Ron Ron" with ease and energy.

Little Anthony also helped redeem the evening. Though he mentioned an allergy problem, his boyish tenor was faithful to numerous hits, especially "It Hurts So Bad" and "Goin' Out of My Head." His polished, good-humored show ("don't call me Little--I'm 41 and a grandfather") was a far cry from rock 'n' roll, but it was nonetheless refreshing.