[Sharon isn't questioning why, she's just going for it, leaping for Natasha and twisting, not only to make herself a smaller target, but to build up some momentum behind the hit she's launching at Natasha's neck. Forget the woman's head for now, Sharon needs to get Natasha subdued and fast if she wants to keep everyone here safe, and the easiest way to do that is to cut off the bloodflow to the brain.]