Hey @Lapdog.
My post was friendly post just to say my wife and I did similar by train to your good selves.
I was very impressed by the power of these electric locomotives by virtue of the speed and ease they appeared to pull the 24 carriage up 1 in 8 inclines.
I mentioned batteries because there were none.
That's not to say lugging a few tonnes of batteries on board up those inclines is not a show stopper.
The tour guide made mention of all the power lines all over the Alps and the fact there were so many hydros pumping out the power we were using at the time.
Actually, those power lines were a visual pollution of the surreal landscape.
