You are correct, rereading my post I did not say what I meant to say. What I meant to refer to was the book value of the reserves that are not extracted. You

You are correct, rereading my post I did not say what I meant to say. What I meant to refer to was the book value of the reserves that are not extracted. You stated > 80%+ of their reserves, and therefore their book value, must stay in the ground. That statement, to me, clearly says the oil that "must stay in the ground" is worthless, and demonstrates that you do mean permanently. If you didn't, the book value of the company would not fall by the same amount as the fraction of reserves, because those reserves still have diminished value at lower rates of production.