Plot hole: In the first season, Lucy Ewing had an affair with Ray, the farm hand at South Fork. Several years later, it was revealed that Ray was actually Jock Ewing's illegitimate son, making him Lucy's uncle. However, the subject of their affair was never raised, even though they surely would have been at least somewhat traumatized upon learning of the accidental incest.
Revealing mistake: At the start of every episode, during the credits, you can see the shadow of the helicopter filming the aerial scenes.
Answer: No, back then such things were unheard of. Too much politics, contract disputes and what would the characters do if they met.