Yarr, the third kerb
Fact is, it doesn't matter at what point he got back on the throttle, he had already managed to be back in control of the car by the second kerb. But because he's a punk bitch, instead of continuing the line he deserved, he back off and caused that spin all by his lonesome. His inability to assert himself manifests itself on track and pigeonholes him as an easy target
Webber blasting past certainly helped him into the spin, but he did not cause it. You wouldn't imagine Webber trying that on Alonso or Lewis
Also i agree, webber deserved an earlier drive through, but thats somewhat unrelated