The anterior border of a palatal major connector should not follow the valleys of the rugae because this area is highly mobile and sensitive. Placing the connector along these valleys can cause discomfort, irritation, and potential trauma to the delicate mucosa during function. Instead, the border should be positioned either on or anterior to the rugae where the tissue is more stable and less sensitive, ensuring patient comfort and prosthesis stability. Avoiding the valleys allows for proper adaptation without impeding tongue movement or speech.

Reference: Prosthodontics: Principles and Management Strategies, Sharry, 3rd Edition.