In the 1970s I learned how to hold down two notes an octave apart with thumb and little finger while playing a chord inversion or running melody notes with the other fingers, also while playing a walking bass with the left hand.
Recently I had another go at this - fairly successfully, only I can't do the bass at the same time. So Retro Rock is a nod to the past with much of it laid down first, and the 'party piece' played on top of it.
Will Godfrey has been involved in music in one form or another since childhood, starting with early piano lessons and progressing through accordion, guitar, harmonica and tin whistle. Eventually, combining his electronics background he moved on to synthesizers and currently soft-synths.