You are neglecting one very important point.
The bikes have changed a lot.
With the switch from 500s to 990s, it became easier for a rider with B or B+ talent to win races... because the bikes were easier to ride in general.
With the switch from 990s to 800s the additional layer of electronics allow riders with even less experience and talent to win races if they have the right electronics and tires. Also- lower top speeds make for shorter braking distances making less passing possible in the braking zone.
The advantage that Rossi's talent provides him has been reduced every year since the 500s went away. Right now the keys for victory are HP, cornering speed (grip) and electronics.
Stoner's bike was right at the top in all categories.
I feel certain that Rossi, Hayden, Pedrosa, Melandri, Hopkins or Vermeulen ALL could have won the championship on Stoner's bike and tires.
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