The long hose is for the octopus.
If anyone is using Air 2 or something similar then you will have to tolerate your buddy breathing only inches away from your face.
The FFM is a lot heavier so it will eat away your precious allowance.
I think we're one the same page, but hung up with terminology....
We don't have octopuses in tech diving. The long hose is the primary in which I breathe off of normally, and is the thing I donate in an emergency, as I know it's working. It hasn't been clogged with rocks or mud. The OOG diver knows it's working, because I've been breathing off of it for quite some time. Which brings a bit of piece of mind. Usually, a necklace of bungee holds the secondary regulator just below the chin.
An Octopus is typically bungeed somewhere on the right side of a body in a recreational rig, usually pretty low by some sort of retainer. It could be cracked, broken, filled with mud, rocks, sand, etc. It may or may not work. You and your buddy really don't know until he has taken that first breath. In using a FFM, this octopus would be what is donated to an OOG diver.