(Thanks for moving the posts to a new thread. At first I was upset to get an alert that my post was deleted, but now very happy to see it was all moved here. Good job mods.)
This whole thing comes down to the manual vs. automatic philosophy. On one side we can argue that OC computer alarms (or eCCRs) are better because humans often fail due to "human factors" - distraction, narcosis, stress, etc. On the other hand, we can argue that machines are unreliable and humans need to constantly monitor them - and features that reduce that monitoring requirement invite complacency that can eventually kill when the machine fails.
I don't really know where the truth is on this, but I tend a little bit more towards automation. I think human factors are the bigger risk. But I could be convinced otherwise. Maybe it depends on the diver.