ALT+TAB:ing out of the game during the loading screen speeds up the loading process?

[Katulobotomia 10]

I noticed that the game loads the map very fast, but then I am put into a second loading bar that fills incrementally each second and doesn't seem to load anything. First, there is the first loading bar that fills almost instantly, then the long second one.

I started ALT+TAB:ing out of the second loading bar that fills slower and noticed that I can load the game and map twice as fast by tabbing out of the game during the second loading bar. Is this a bug or what? It feels like there should be an intro playing on the second loading bar, but there isn't and there is no other way of skipping it other than tabbing out and back in.