Don’t let your “fanboyism get in the way”. To say Petrov shouldn’t have stayed ahead of Alonso, because he was slower, goes against everythng related to racing.
If Alonso was so much faster, then why didn’t he at least tried to overtake? Because the track didn’t allow him to make a move, and because he wasn’t that much faster than Petrov either.
Blame the track (which is perfectly acceptable, as it’s plain rubbish and shouldn’t be approved by the FIA in the first place… but that’s open for another debate), blame the characteristics of current F1 cars, the dependance on aerodynamic grip, whatever you want, but not the defensive moves (or the lack of them… Alonso simply couldn’t get close enough).