Re: Has Jelena improved her serve?
It's because shoulder rotation is a given ability. You can make technical adjustments to a serve, but if the player has slow shoulder rotation, then they'll never have a good serve. Of course, there are players like Henin who just had bad technique, but others have no scope for improvement.
It's not that players like Dementieva, Chakvetadze, Jankovic, Hingis and Hantuchova are too stubborn to make changes, it's just that they have already reached full capacity.
Casey Dellacqua, Jelena Jankovic, Anna-Lena Groenefeld,
Jelena Dokic, Mirjana Lucic, Sara Tomic, Sloane Stephens
Melanie Oudin, Kiki Bertens, Kaia Kanepi, Alison Riske