Ferrer doesn't have the nerve Nadal does, but equally important is that Wawrinka is likely to play better on clutch points against Ferrer than he would against Nadal. Were Wawrinka as intimidated by Ferrer as he is by Nadal, Ferrer's chances would be higher.
I don't agree that it's a pretty fast court at all. The bounce seems to me medium-height (which is high for an indoor court) and, more importantly, pretty dead. I don't see it moving through the court much. Then again, I'm not a Nadal fan, so I suppose you'll discount that opinion!
Anyway, even though Wawrinka has more firepower than Ferrer, I think that, in a matchup between the two of them, Ferrer benefits from increases in court speed, and not Wawrinka. As it happens, slow courts often favor the player with more firepower off the ground, because on faster courts even someone with less firepower can hit through the court to some extent. (The Gonzalez v Murray match at Roland Garros 2009 is a great example of a player with a lot of firepower benefitting from a slow court against a player with much less firepower).
