Funky, jazzy, groove that explodes into polyrhythmic madness...actually even though we are all practically playing in a different time signature the syncopation feels like it grooves in 4/4. Well that's my opinion.
The groove with the bass in 5/4 over a 4/4 backbeat was something that was improvised during a jam session in the cretacious period. Needless to say it has evolved into it's current form.