For anyone that hasn't read about the reason behind the phenomenon, this is how it goes very simply:
If you knee animation COMPLETELY finishes right before you touch the ground, then you can do a double jump again if you press jump a little before the end of the knee animation (thus buffering the jump). Pretty much it doesn't do much at all. I was hoping it would allow us to jump-cancel the laggy part of the knee as we land,but it doesn't do that. Since your knee has to be finished and you have to be nearly skimming the ground already, there's almost no point in trying to set this up, simply performing a jump as you touch the ground works virtually the same.
It's also incredibly hard to perform intentionally. Howver, if you get in the habit of hitting jump as you land from an aerial (like L-canceling with L or R in melee) then you may be able to produce this on occasion just by sheer luck/randomness (it might help for stringing nairs together maybe?).