Please allow me to advertise my ignorance..,
What the heck is it? I could only think that one may put two different weak colonies in two different supers separated only by a newspaper. It's either chewed through or yanked out later by the bee keeper. Am I close?
That's pretty much how it works, no need for the beek to remove, they will chew through it and carry it out the hive within a couple of days.
There are diffenent theories....some use multiple pages, some spray it down with sugar water, etc. etc.
I've done a few, I use just a single sheet of dry newspaper with a few slits made with a razor knife or hive tool. I've always cracked the top on the top box to give the bees in the top box a way to battle the heat until the colonies are joined....all have worked fine.
It's amazing to observe the piles of shreaded newspaper accumulate outside the entrance to the hive.