From her interview yesterday:
Q. It certainly was strange. As far as Venus' game and maybe Serena's also, how much less intimidating do they seem now than maybe two, three years ago?
AMELIE MAURESMO: Well, they don't win as much. Again, you are talking about two, three years ago. Serena was winning all the ‑‑ I think she won the four Grand Slams in a row, not in the same year. And then Venus> in the final each time.