Re: why do women double fault more than men?
Its all in the wrist. Most women don't have the wrist strength to generate consistently heavy kick serves. Serena and Molik are good exceptions.
Which is why Venus's second serve is all that more frustrating. She has no business hitting 120 MPH first serves and not hitting heavy kickers for the second delivery.
Thats another thing, women emphasize MPH, rather than spin. You might see a Nadal hit second serve averages around 90, and a Justine at 90, but the former has way more spin on it. The women would be better served learning that kick, albeit at maybe 75 MPH, than just hitting it hard and hoping it goes in.