If memory serves me correct, I believe Merc said that they gambled on a wet race. As such they put on a wet setup. While RBR and McLaren had gone for an "in-between" setup.
What this meant was that in the wet, the Merc was indeed fast. But the moment it started to dry, the RBR and McLaren cars were much much faster and MSc got eaten up.
Would MSc be able to beat Button in a wet race, fair and square?
I think it is has been proved beyond reasonable doubt (over the last few years), that moment the track is wet, Button, for whatever reason, begins to move up places. When Hamilton hadn't been "broken", he would beat Button almost every time in a dry race, but in the wet races, Button was the boss. For evidence of this see the first 4 races of 2010 (2 of them were wet and Button was leading the title race...we then hit the dry races and Hamilton usurped him).
If you check every single wet race over the last 2 years, comparing Button with MSc - there is no comparison...Button has an uncanny method of moving up the field. MSc does not possess this ability.
Don't get me wrong, in his first career, MSc was daddy of F1. He was the man to beat. Even when Alonso beat him in 2005, MSc was still the daddy. But the moment Alonso beat him in 2006, MSc knew the game was up and decided to call it quits...the mantle had passed on. In his 2nd career, MSc is not the same driver he was 10 years ago.
