Rating drivers on stats like that is bias. The cars them selves also have a part to play. Don't think any one can deny that the Red-Bull is fast in clean air, that's why the did so well last year. Behind another car though they struggle. Their fast in corner and slow on the straights, a trait of how the car was designed, but still making overtaking hard as you cant over take in most corners, either over take into the corner, need straight line speed, or get better drive out of the corner, but then still hampered by straight line speed. Webber last year had a shock, over one lap they were close, but Webber got stuck in traffic and couldn't do anything. In clean air he had quite a number of fastest laps. Also what's to say that the drivers don't use their cars to their max in quali, last year Hamilton had a few blistering qualifying laps then when it really counted he made small errors costing him. In that sense he didn't put the car where it belonged but come race day over 50 odd laps with a faster car he can over take slower cars ect.
Hell look at schumi last year, he had the most in race overtakes purely because he lost his front wing so many times and had to retake positions from slower cars.
What I'm getting at is that you cant rate drivers on stats, there are more variables involved.
On to Pastors win, one hit wonder IMO. He hasn't really shown any hint of being a top driver. Williams was a fast car trough out the weekend, and he did do well getting that victory, but average driver at best he didn't have much on good old Barrichello