You’ve made a great point.
If they were already in the process of upgrading the pad with a deflector and cooling they must have known there was a non-zero chance of causing serious damage to the rocket. SpaceX employs some of the smartest people in the industry, but they can all be outvoted by a man with a juvenile sense of humour.
And this setback means that the Moon landings will be delayed even further. I bet NASA is quietly furious that SpaceX didn’t take proper precautions to safeguard the rocket and pad.
Liquid-fuelled engines tend to burn very slightly fuel rich to eliminate the possibility of having excess hot oxidiser run rampant with the materials of the engine. That’s why kerolox rockets leave a slightly sooty trail.
Having said that, last week’s launch was very much engine-rich.
