Nothing says she might be the one like a dazzling nonengagement ring. The Bachelor's Bob Guiney proposed, er, a relationship to Estella Gardinier with a two-carat Harry Winston bauble. ''I sensed some ambivalence, so I suggested the right-hand ring,'' says Winston rep Carol Brodie. ''Then he was really psyched.'' Bringing the promise-ring tradition back for commitment-phobes everywhere.