The interesting thing to me is that Hubbert's (basic) model seems to have been pretty accurate, as the 1956 prediction looks to have been sometime around the year 2000, as opposed to the current predictions of some time between 2010-2025.
Its utility as a theoretical construct was demonstrated by the accuracy with which it was able to predict the US peak. Of course, there's always that pesky discrepancy between the theoretical and the real-world, and since global politics and economics are a bit more complicated -- and these do influence production and hence the point of peak production -- predicting the
global peak is a correspondingly less perfect science. The qualifying phrase, "if current trends continue" soaks up a lot of potential error. Unlike the global discovery peak, the
US discovery peak was well in the past by 1957; the arab oil embargo (and the massive conservation it inspired) hadn't happened yet; OPEC and its production quotas (and the dubious reserve estimates they inspire) didn't exist.
The equation now has so many variables that it's hardly surprising to see projections all over the place, but it's worth noting that even among the minority of experts who question the validity or the applicability of Hubbert's model (favoring, say, the "undulating plateau" over the "roughly symmetrical curve") there are very few who predict an endless (let alone an endlessly increasing) abundance of oil, and (with the exception of a handful of cornucopia loons like Jum'ah)
none who predict an endless abundance of
cheap oil.
That last point is important, because a lot of the criticisms of peak oil theory are based on anticipation of the development of new technologies that will make it possible to extract oil from sources previously regarded as unrecoverable. As soon as one redefines "recoverable" in this way, the size of remaining reserves changes, and when those new estimates are fed into the model, the projections change. It's not a given that those updated projections are more accurate. If they ignore EROEI, they are almost certain to be unrealistically optimistic. It's easy to forget (apparently) that horizontal and deepwater methods and so forth consume more energy in the extraction process itself.
If those projections
are more accurate, it's because the shape of the curve itself has changed; the actual peak point has moved to the right, increasing the steepness of the downslope. It could buy some time, and it's tempting to see that as an entirely good thing. We could use that time to really get on the ball with alternative energies and conservation and optimization and all that, smoothing the inevitable descent. But it also increases the pressure to be successful in those mitigation efforts
while at the same time making it even more difficult to muster the political will to implement them, because it will surely create the impression in the minds of a lot of people that the crisis has been
solved by technology rather than merely delayed.