Old and Modern Pinpoint
Phillipousis, Ivanisevic, and Ljubicic all use pinpoint if I'm not mistaken.
Just checked youtube videos.
Lubicic looks Pinpoint. Begins with weight all on back foot.
Ivo does NOT bring his back foot forward, so he is Platform
Mark does bring his back foot up but only because his back foot is so far back to begin with.
However he does move it forward [but not next to the front foot].
So he is more or less in between Platform and Pinpoint
Maybe I am stretching here but ..........
I think a distinction could be made between old school pinpoint and modern pinpoint.
Old school pinpoint was for serve and volleyers who learned to lean forward falling in to the court.
This pinpoint is all with weight forward both at start and finish.
Tim Henman is a good example of this.
Modern pinpoint has the weight way back on the back foot to start [Phillipousis, Lubicic]
and then naturally they must move the weight forward.
Platform gets a lot of power from the back leg
Pinpoint gets most of its power from torso turn and the arms.
Pinpoint is best for short players who need to get up as high as possible.
I think the most powerful serves are Platform.
JMHO