Ah, well that's where I'd disagree. Surely nobody can dispute that Ve&Se are the fastest two players on the tour. Who is the fastest of the two, I really can't decide, but that's all moot.
But when seeing either of them play Capriati, Clijsters, Henin, Dementieva, Myskina, Mauresmo, it's clear that speed is not where those players are overwhelmed. I'd say Venus and Serena are only marginally quicker than those players.
And people sort of missed my point a little bit...
People are looking at their injuries in the short-term. Continuous injuries are disheartening and it's not as if the Williams' don't have distractions. How much longer are they going to be prepared to lunge all over the place for shots then take a month, two, three or six out and have to start from scratch.
I think it's highly possible that eventually, and in not too long, we'll see them taking fewer risks. They'll still be phenomenally quick, not to mention powerful, but unfortunately I can only now see Venus and Serena beginning to slow down.
They just can't continue getting injured like this and expect to have full-time careers.