>Why there weren’t mechanical limits on the control rods equipped with followers or other system interlocks is beyond me.

I believe the answer to that is in the book "Atomic accidents" By James Mahaffey. Apparently there actually were safety systems like that, but in preparation for the safety test they had a special switch installed which disabled them.

I've always heard that black holes slowly "evaporate" in Hawking radiation over an astronomical long time, but I also heard that time slows down in gravitational fields.

So could a black holes slow hawking's radiation just be an explosion, which is "slowed down" by the black holes gravity, so from the outside it seems to be exploding "really really slowly"?