Personally I think this is all about
regression towards the mean. There are many better statisticians on this board than me so someone can probably analyse this better, but it's a pretty well known phenomenon that sportsmen and women have their statistical good seasons and bad ones, and that judging results by one or two races rarely provides a good picture. So Button last year had a period where everything came together for him and it was enough to win him the championship. That's not to say he didn't deserve it but he's generally a top 3-5 driver and will probably settle back into that, barring the odd race where things go his way again, as we saw at the end of last season and the start of this one.
Personally I think that Webber probably has a much higher amount of talent than his stats might reflect. It's not unkown for sportspeople (or city traders or even
movie producers) to have very long runs of good or bad luck and Webber seems to have had far more than his fair share over his career. If that run is over and it really has been masking his true talent then absolutely he can, and probably will, do it. On the other hand the four wins could be the statistical blip and he'll slide back down the standings over the next few races.
So can he? Yes. Wil he? Who knows but I'd be very happy to see him take the WDC and it seems to be looking good so far.
Matt.