See the video linked in JackBurton's post below yours. Notice how the the video feeds of the minimaps on the slaves look the same as those on the main? If I understand things correctly, trying to do that with your setup would result in very low-res minimaps because the windows supplying those feeds are small. With the setup I describe above the feeds are at the same resolution as the main window (as they are in MiRai's video) because they are as coming from full-size windows.
Unfortunately, that means you lose the little windows along the bottom of your screen (they are now large and behind your main window). But fortunately (or by Lax's great design), you can recreate them using video feeds. That is much of what I describe in my guide.
That's about the best explanation I can give you. Maybe someone else can have a go at making it clearer.
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