That was an interesting read; he wasn't even very confrontational there. The point was also solid - they had an internal performance optimization change which was unproven, yet broke things in the real world. That, and the lack of guidelines or tests for what kind of usage results in the behaviour, it's a de-facto "feature" of the interface that they should not break.
I do wonder what the correct workflow is for preventing this - release binaries with assertions in place for development, so that if any of your input constraints are violated that aren't guaranteed to fail fast in the release version, then it's enforced in this debug version?