Thanks for the clarification. The analogy to multiple references (with ≥1 of them allowing for mutation) is an interesting one, though I don't quite understand

Thanks for the clarification. The analogy to multiple references (with ≥1 of them allowing for mutation) is an interesting one, though I don't quite understand why having that would imply a need for locking the same mutex multiple times. Will read up on the "access requester" mechanism though.