Comment by GMoromisato

> the agency said it was confident that a change to the re-entry trajectory would be more than adequate to offset any spalling issues. Somewhat confusingly, they also announced their intention to switch to a new heat shield design, starting with Artemis III.

This is not confusing in the least. Engineers don't talk about safety in binary terms. It's not "safe" vs. "not safe". Instead, it's all about the probability of a bad outcome. At NASA, they compute the probability of Loss of Crew (LoC) and the probability of Loss of Mission (LoM).

For Artemis II, a change to the re-entry trajectory brings the LoC/LoM back to an acceptable level. For Artemis III, which a new shield design, they can get to the same LoC/LoM with a different trajectory (which gives them other benefits).

Stop thinking in terms binary terms. Everything is a probability.