Whisk together the reduced-fat mayonnaise, mustard, salt and black pepper in a medium-size bowl until well blended. Gradually whisk in the olive oil until thoroughly blended. Cover dressing and refrigerate until ready to use.
Fold together the cooked chicken, one third of the mayonnaise dressing and one third of celery in a medium-size bowl. Cover the chicken salad and refrigerate for at least 1 hour.
In a second medium-size bowl, mix together the cubed shrimp, one third of the mayonnaise dressing and one third of the celery. Cover the shrimp salad and refrigerate for at least 1 hour.
In another medium-size bowl, mix hard-cooked eggs, remaining dressing and the remaining celery until well blended. Cover the egg salad and refrigerate for at least 1 hour.
To serve, toss together iceberg, romaine, radicchio, carrot, radish, tomatoes and the vinaigrette. Spread over large, deep, oval platter. Arrange chicken, shrimp and egg salads in mounds over greens. Serve with the potato rolls.
