This is supposedly just one of several.
I read a book 30 years or so ago about how during Ike's Presidency the decision was made to keep secret lots of heavy duty deposits--and to not use them until the rest of the world ran out of oil.
I don't doubt that something like this could be true. Whether it is or not remains to be seen. And why are the puppet masters allowing it out, now. To forestall the zero-point energy technologies from being outted?
We shall see.
That has a bit of a 'tin foil hat' ring to it. How about this alternate wording:
not to use them until "the cost of oil had risen to such a level that they could justify the much higher extraction costs"
We are nearing or at that point today, as witness the developments in Alberta. I would guess we are 5-10 years away from serious development in shale oil extraction.
In this part of Ohio we have had several oil booms (and busts) over the past 100+ years, and thus we have a fair amount of oil producers. I've talked to several of them and they all say that the US govt policy is to preserve as much of our oil as we can---just as you say---for the day when the others run dry.