I was assuming the self-healing clusters in their setup would operate using code not produced with stability in mind.
"Also the blog post says nothing about integrity. It does not seem that integrity is affected."
I was assuming that the code that maintained integrity had to run correctly and stably in order to maintain integrity.
EDIT to add: Recall this played out in filesystems and regular databases where software errors could corrupt things. Now, just imagine same thing for distributed programming. Same or worse results from defects as always.