My impression is that this kind of defensive behavior should not be tolerated. Cutting a chicane when you're defending track position against a pursuer is not acceptable. If there was a wall in there, the driver wouldn't be cutting the corner, but if there is none, they may just jump the chicane and ensure that they're not overtaken then and there. If you cut a chicane in order to avoid being overtaken, you should yield your position to the driver behind you. Shame the stewards don't agree with my views.