I do - I much prefer using computers with only one window visible. And use all the keyboard shortcuts (tab, window and desktop switching) to rapidly change what the thing it shows is.
I reckon there's something interesting about human variety in focus and/or visual processing this tells!
I, on the other hand, use the keyboard shortcuts to adjust the browser width to achieve the desired line width and line start, because even when the web page takes care to set these, it varies from site to site and rarely is what I want. (For sites I visit often, I use window manager automation to auto-adjust the browser window size.)
I reckon there's something interesting about human variety in focus and/or visual processing this tells!