One quote that stuck with me is "On reaching the 500 km/h mark, the camera controlling the pantograph condition already shows a continuous electric arc" - you c

One quote that stuck with me is "On reaching the 500 km/h mark, the camera controlling the pantograph condition already shows a continuous electric arc" - you can imagine that under these conditions the wire will wear down much faster than with "only" 350 km/h. So, before reaching a physical limitation, you already reach an economic limitation...