Hi Reuben
I am no expert on these but what I do know is these power mowers were an item only available to the very affluent in the early days - hence those who bought them normally had gardeners/servants.
Hence a selling point was that it can "save on labour time - mow 'x' yards per minute" - without really worrying that the poor bugger behind the handle is getting pulled around
This attitude and advertised 'feature' did expend to even later models like atco and qualcast, especially 2 strokes