Some artistic ideas end up looking better on paper than elsewhere. Such is the case, I think with Jan Van Dyke's "A Pastoral: How the Blind Shepherd Gains His Sight From the Good Fairy (With Talking Sheep)," a dance fable whcih Van Dyke and her troupe presented for the first time will be repeated daily through Nov. 5 at the Renwick Gallery yesterday.

The concept was fine - to choreograph for the beautifully appointed spacious Grand Salon of one of the city's handsomest art museums. A few years ago, Van Dyke created one of her most imaginative, fully realized works, "Ella," using a broad staircase and two large spaces of the Corcoran.

"A Pastoral," however, founders in a bog of fey preciosity without uncovering any compensatory chores graphic or theatrical interest. The dance is an archly "innocent" charade the plot of which is completely described by the wordy title. The children's book costumes by Terri Hume Prett are charming and indeed the whole thing may offer some mild amusement for very young viewers. The minimally sketched roles, however - Elly Canterbury as the Good Fairy: Virginia Freeman and Van Dyke as the Talking Sheep; Susan Sachs as the Blind Shepherd - do little for adult sensibilities beyond showing off the presence and fluidity of the dances. Most surprisingly the choreography takes scant advantage of the Renwick space or ambiance.