Born In The Melbourne Music Scene Of Early 1970's Australia MacKenzie Theory Played A Brand Of Instrumental Jazz-Rock Not Unlike That Of Mahavishnu Orchestra Tempered By It's A Beautiful Day. The MacKenzie Theory Sound Was Centred On The Inventive And Fiery Guitar Playing Of Rob MacKenzie Teamed With The Electric Viola Of The Classically-Trained Cleis Pearce Mike Leadabrand On Bass And Andy Majewski On Drums.