Earlier quoted context omitted.
> After that, they still have a fair way to go on Raptor reliability I suspect the debris from blowing a whole in the ground was the biggest contributing factor for the engines out. It looked like at lease 4 we're gone before it left the pad.
Isn't it pretty unlikely that this debris, flying against the exhaust, can reach the engines with significant energy?
But looking at that pad and the damage to it- without deluge dampening, I bet the RC spalling might have been a bigger issue than just ground blowback.
Put a blowtorch to some concrete a and watch how quickly trapped moisture starts causing miniature explosions and flying shrapnel.
But that's just my first uninformed impression.