I have a very different concept of nirvana that correlates with how you describe the narrowing path and it is why I cringe at those selling enlightenment but maybe I shouldn't see them as synonyms and in any event I wish people would stop egotistically claiming to have achieved enlightenment and simply say "more enlightened." I quote my Rama in many of my essays: "To attain nirvana, you would go on a completely different cycle, and that usually happens after a vast number of lifetimes lived. The lifetimes that you start to choose to live [at that point] are with great suffering. Think of the severely retarded, the severely mentally ill, POWs, people who have died violently at the hands of great evil and even stillborns who give up their life experience for the host."