It cuts both ways. What I usually do these days is to let codex write code, then use claude code /simplify, have both codex and claude code review the PR, then finally manually review and fixup things myself. It's still ~2x faster than doing everything by myself.
100%. On days when I'm sleep deprived (once or twice a week), I fallback to this flow. On regular days, I tend to write more code the old school way and use things things for review.