Paul means historical in the sense of where we came from, a triple La Nina. He says the turn around from LA Nina to a strong El Nino of this magnitude in the same year is unheard since 1870's.
Paul does not expect an El Nino of the magnitude of 2015-16 but does expect ONI to top 2.0 for one period either NDJ or DJF.
They all have strengths & weaknesses. Personally, Iike: Euro, UKMET, JMA, & CanSips. Blend the 4 in Nov & roll with it.
I'm 100% not a fam of the CFS. It's eradic. It's monthly forecast is sometimes good.
I'll throw this out there, just for interest & fun. Paul Roundy's MJO tools showing a big -EPO in early DEC:
https://www.atmos.albany.edu/facstaff/roundy/waves/rmmcyc/indexmjo.html
CFS has AO going negative for entire month which is most of the time a good indicator of PV staying relatively weak. Now, there could be major decoupling & that not be true.