I'll second that - you cannot use Acrobat's APIs (regardless of whether
it's the IAC, JavaScript or the plug-in interface) without having access to
the documentation. I've worked with the Acrobat SDK on a daily basis since
for a long time, and I still use the documentation almost every day.
That's why my article actually refers to the SDK. You need to download and
install the folder level script that defines this function before you can
call it. Again, the SDK is your friend here and explains how to save folder
level scripts.
In order to use the JSObject, you need to have a good understanding of both
the JavaScript API and the IAC API.