One thing that I have learned is that you have to master the art of nuanced thinking with respect to seasonal forecasting...a couple of years ago, I would have only considered basin-wide, mod-strong el Nino analogs, but I have realized that it makes little sense to be so restrictive based upon only ENSO when there is such a wide assortment of factors working in concert around the globe to consider. This is why now I will also consider what has actually happened in terms of temp and precip patterns and potent el Nino seasons like 1982 and 2015 had value...1997 did not, IMO.
Rigidity is your largest foe in seasonal forecasting....any forecasting, really. Keep an open mind and try with all of your might avoid becoming married to any single ideology.