Here is a business article that explains why it's nice to be able to predict ENSO
The comparison is what would happen if we didn't have a model for tides. Wouldn't know when or where you could moor your boat or when you could launch it. But with ENSO, the stakes are much higher, as economies and agricultures are sensitive to the phase of ENSO.
This is my latest ENSO model that uses known angular momentum variations in the earth''s rotation (14 and 6.5 years) along with the known lunar periods that give the lunar tractive forcing extremes. It's essentially a tidal model reconfigured for the sloshing of the ocean, which if it portrays the actual physical mechanism would be a breakthrough for climate prediction.
The distinction with the QBO model is that lunar terms are strong second-order factors in ENSO, but first-order with QBO. The angular momentum changes are irrelevant for QBO as the atmospheric mass has very little inertial mass.
It will be a learning experience to see how this tracks both into the past and into the future. As I mention [here](http://contextearth.com/2016/09/09/obscure-paper-on-enso-determinism/), Hanson,Brier,Maul have established that the strongest periods going back to 1525 are 14 and 6.75 years.
The problem with historical proxy data is that the highest resolution is essentially 1 year (for measures such as tree-rings & coral-rings etc) but for proxy measures based on sedimentation results, the resolution is much worse. It would be nice to have the extra resolution for proxy like we have for instrumental ENSO records (monthly pressure and temperature readings) but doubt that we ever will get that.
There is an _xkcd_ cartoon that has gone viral recently that doesn't acknowledge the smearing of the proxy data. One paleoclimate guy was pointing this out and it is [covered in this NPR piece](http://www.npr.org/sections/goatsandsoda/2016/09/14/493925781/epic-climate-cartoon-goes-viral-but-it-has-one-key-problem).