One thing that bugs me about the final example is the markup is not indicative of the layout, which is something I try to adhere to. Screen readers will jump to

One thing that bugs me about the final example is the markup is not indicative of the layout, which is something I try to adhere to. Screen readers will jump to content in the order of left sidebar -> right sidebar -> main content, while most frameworks float everything left and fill the space, so that a screen reader and the markup would read from left to right.