Mark's luck with RB has been pretty staggering. For both Lewis and Mark - if something can go wrong at exactly the most inopportune moment, it will.
I was sitting at turn 10 yesterday and you could easily, easily see Vettel on the power 6-7 car lengths before anyone else. Watching that corner made me realize that Vettel's success comes from not making mistakes - but his luck is phenominal, and his car is without a doubt in a completely different league to the others. And because he doesn't have to drive it on the edge just to be competitive I have to assume it's that much easier to not make a mistake.
It actually took a lot of enjoyment out of watching F1 seeing that disparity so obvious. I can only hope next year's changes shake things up.