What happens if theres no human in charge though? I'm thinking of various
completely automated systems such as Line 14 in Paris & various VAL systems
around France. Could a derailment (or whatever you call it on rubber tyred
systems) happen on them without power being lost? If the DLR was run in the
same way and no one in charge was on board we'd probably be looking at a
very nasty accident.

To be fair the report implies that if the operator on the train was
indeed responsible for the emergency brakes being applied (and they
can't be 100% certain because - wait for it - the CCTV on the train
wasn't working), then he likely only beat a number of automated trips
by a second or two.

Of course, the report also points out that risk of a derailment in
which the train DIDN'T stop automatically, twisted and collided with
either an oncoming train or station infrasture had ALREADY been
assessed as the train-related incident with highest risk several years
back and that despite making concerned noises Serco and co. have still
done bugger all about it.