When serving, most, if not all, current top ranked pros land momentarily on the undominant foot and then almost immediately land with all of their weight on the dominant foot. Right handed players land momentarily on the left foot and then on the right foot. Left handed players land momentarily on the right foot and then on the left. Boris Becker was the last player that I can remember that landed on the dominant foot (his right) without first touching down on the left foot. This style of landing results in the feet being crossed with the dominant foot in front when a stop-motion photo is taken at the moment of ball contact. Years ago, when this technique was more popular, there were many photos of pros in that crossed foot position. Someone once told me that landing on the dominant foot makes the serve harder to control. I tried it and it gave me alot more power but the serve was indeed harder to control. What is the reason for this style having disappeared?