Actually, the evidence, the decline in production since December by the top exporters, especially Saudi Arabia, supports HL method.  Stuart is expressing an opinion that the method has errors (depending on where a region is along the linear plot), but the evidence, e.g., the US, Texas, Russia, North Sea and now the world and Saudi Arabia support the accuracy of the method, especially at or beyond 50% of Qt.

The key point is that the world and Saudi Arabia have shown strong linearization patterns for quite a while--which makes the predictions much more accurate.  Both regions are at or past the 50% of Qt mark.  The HL method was 99% accurate in predicting post-1970 Lower 48 cumulative production, using only production data through 1970 to predict future production.

I would go back to my example of the Lower 48 versus the North Sea.  The two producing regions could not be more different, but they peaked at the same stage of depletion.  We find the big fields first--that is why we can compare the Lower 48 to the North Sea to the Middle East and ultimately to the world.