It does this:
Creates an ini entry in Macroquest.ini that performs a command automatically after entering world. This may be 'deprecated in favor of .cfg files.
So, let's say you did /set /hidecorpse all
Then it would do a /hidecorpse all when you entered the world.
I imagine you could /multiline to add a few commands. CFG files would work better in my mind, that is what I use.