It's worked pretty flawlessly for me. PC has had major issues though.
Try it near a ritual stone, it won't work in Vagrant's Rest (the town itself), you have to be at roughly the same point in the story (i.e. which bosses you've beaten).
Beyond that, wouldn't know what to recommend. It can be convoluted admittedly, but A44 have decided the passive MP experiences are worth more then the simplicity of adding friends directly.
I get why passive is cool for when you aren't playing with a friend. Or for a game where it makes sense like Journey. But by default, in this game you always have someone with you whether it's a real person or an AI. Even dark souls makes sense since you are summoning some other soul into your own game. The fact that they needed to release an FAQ tells you whatever they were going for needed to be explained better.