So reserving the champion status to specific drivers.
Not specific drivers.
If a driver like Webber (who is average), performs out of his skin in any given year and is the best driver/car package, then of course he deserves to win the title. But to win the title simply because your team-mate's car keeps breaking down isn't right.
There is no rule that states that a driver who is performing poorly, cannot up his game. Button did this in 2009, where in 2008, he was beaten by Barrichello. The following year, he upped his game and comprehensively outperformed Barrichello. He won 6 out of 7 races that year and rightfully won the title.
Webber on the other hand is getting beat in pretty much every race, by Vettel. In every race he starts, he is (realistically) aiming for 2nd place, behind his team-mate because his team-mate is untouchable.