Khebab, correct me if I am wrong but I think the oil shock model still has predictive value in that if you extrapolate on current knowns, then shouldn't the resulting picture be the most optimistic scenario possible (i.e. one lacking any further shocks)? So doesn't the oil shock model set upper bounds on what we can expect from production barring further shocks?

Ghawar Is Dying
The greatest shortcoming of the human race is our inability to understand the exponential function. - Dr. Albert Bartlett

The issue is to find a way to extrapolate the model parameters correctly.

Of course, we can't predict future oil shocks (i.e. the predicted curve is smoothed) because the extraction rate is staying constant.