It is always better to focus on clearing karma, nirvana if it is the ultimate state will only be achieved that way anyhow... but many western occultists disagree with transcending the lessons of the physical plane, whats the point of being here if you are just going to skip over them to nirvana? Yes duality in the sense that balance is the key to resolving opposites
When Kurt Cobain blew his head off with a shotgun, I guess he removed Nirvana from the music scene. He must of had some weird karma resting on his poor soul don't you think?...