I would think that quite a few death certificates have 'old age' given as a reason, with other reasons as well. Does anyone see death certificates as part of their work? I used to, and I've definitely seen 'old age' on them.
There was a time when an English birth certificate would not have the time of birth shown, except, I think, in the case of twins, whereas a Scottish one would have the time of birth. I haven't had anything to do with a death certificate lately. Would the mention of the time be a Scottish thing or do English, Irish and Welsh death certs also have the times on them nowadays?