At 3:31 he shows how to get a natural octave sound by plucking the string at the position of the same note being fretted, but an octave higher on the same string.
What A Trip Of An Ending
Never occurred to me to pick the octave , way cool
Thanx For Sharing There Brother,
It’s basically an anti-harmonic, it cancels out some of the overtone frequencies so you hear more of the fundamental.