When done by the [CLR] I don't think it was about "playing tricks with
energy". Electricity was still a very new form of energy and such
considerations hadn't arisen, it was simply a way of using a natural
phenomenon (gravity) to improve the performance of the trains. ...

As already pointed out, that amounts to the same thing.

I'd just like to note that when the C&SLR decided to do it, they
were expecting their trains to be cable-hauled, not electric.

The energy and performance issues are of course essentially the same
either way. But with cable haulage, a hump gives a special benefit.
The train is accelerated from rest up to cable speed by tightening the
grip until it clamps firmly onto the cable; and while that's going
on, the cable is rubbing against the grip as it slides through it.
So a gravity-assisted start could significantly reduce wear and tear
on the cable.
--
Mark Brader, Toronto | "If gravity stops working, a power cut is
| the least of your problems." -- David Bell

My text in this article is in the public domain.