(Reposted from Groups.io extremeprogramming group)
For those who haven't been watching 3 Body Problem
on Netflix, the last episode of Season 1 includes a resounding lesson
about the difference between Waterfall and Agile. (It would be great
if someone with more video savvy than me were to capture the clip and
link to it here.)
The Staircase Project is the old Project Orion
concept reimagined to send a probe to recon an alien enemy fleet many
light years away. Without going into spoilers, the basic idea is to
accelerate a probe with an EM sail to near light speed by shooting it
past 300 nuclear bombs, each to be exploded at just the right moment to
blast it with radiation. This is a purely ballistic launch: the probe
has no power or steering capabilities, so the explosions have to be
timed perfectly and the trajectory is locked in.
Sounding familiar?
Early
on, the shock of an explosion disconnects one of the tethers connecting
the probe to the sail, the probe goes off course, and the entire
project is lost - a world-threatening catastrophe.
It would not have been rocket science
to give the probe the minimal intelligence and power to adjust its
trajectory, perhaps by "trimming" the sail with a tug on one of its many
tethers. But no: the finest minds on earth agree it's necessary to
lock the trajectory in up front.
(Disclaimer - I've read only the
first book in the trilogy on which the series is based, which ends
before the probe project is undertaken, so I don't know if the author, Liu Cixin, is responsible for the waterfall.)