David Cantrell gurgled happily, sounding much like
they were saying:

In a situation like this, of course, that extra toughness might not
have been an advantage - rather as with giant 4x4s, it may reduce the
danger to occupants at the expense of increasing the danger to those
outside it.

If you assume that the tram will be carrying a great many more people
than any other vehicle that it runs into (an assumption which, IME,
would hold pretty much all the time in Croydon) then that's a good
trade-off.

A quick google suggests that the Croydon trams have a capacity of 200
people and a kerb weight of 36t - so a laden weight of about 50t

Compare that to a typical current double-decker, with a capacity of 60(?)
and a kerb weight of 12t, so a laden weight of about 16.5t

There's also the greater impact avoidance of a bus than a tram - a bus
can swerve, whereas a tram can't - and the greater impact deflection of a
bus than a tram - same reason.