Very interesting.  So you are saying that the leaf mixture along with oils from the plant make more of a difference in the experience than the acid used or the pH it was pulled at? I guess that makes some sense.

Very interesting reading.  BTW I am using phosphoric acid exclusively in my extractions now.  It is easier to handle than HCL and seems to pull more spice than vinegar.

I have not had the problem with oils coming through though...quite the opposite..I have had much fewer oils than any other tek used.  This may be because I am not pulling the spice with hot NP but waiting until everything is room temperature before pulling.

Do you feel that the pau d'arco makes a big difference?  I mean have you tried just using blue/white lotus leaf?