tbh the whole DirectX problem is just a pain in the ass.
It isn't just from doing alt-tab from full screen that causes it.
In my case I use HDMI to connect to my monitor, so if I turn the monitor off while playing the game it crashes with the DirectX error. (Even in windowed)

I don't like just leaving my monitor on when I go afk but I'm pretty much forced to when I'm playing this =/