Here is the video of my presentation at Hyperkult: Back to Childhood - Infantilization of UI Design. After the talk Ivan Sutherland pointed out that the TX-2 was just build to prove the concept of a computer based on transistors. The four black knobs below the screen where not build in specific for Sketchpad; they rather controlled directly the value for four memory registers that Ivan used for scrolling and zooming the image on screen.
Back to Childhood - Infantilisation of UI Design from mprove on Vimeo.
German paper and references: Zurück in die Kindheit – Infantilisierung im UI Design.