I learned a similar lesson from the black crossbar at the bottom (over the black floor). Luckily I didn’t grab the network cable on the way down!
And if you killed the rack? Ah, well, just monkeytesting showing a configuration error. (Bombcar’s law: any dual powered rack will have one critical component that is powered from one rail only.)
OT, but I saw the electrical plans for a hospital. In theory, every life saving device has at least two potential power sources, and each source has both a generator (for long outages) and battery backup (for blips).
In practice, we hope there are no earthquakes.