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.
I often work this way too, but I'll say this:
This flow is exhausting. A day of working this way leaves me much more drained than traditional old school coding.