The All England Club dropped the tradition of a bow or curtsy to the royal box in 2003. That came at the request of the Duke of Kent, the club president, to the relief of most players at the time.

Ladies (and gents) are permitted a bow, or even a (significant) inclination of the head. More than a nod, please. "If you are going for the curtsy you want a straight back, to mitigate the chances ...