I'm not sure I buy that example; if it's a time-sensitive issue, Co-worker can't just fire something off into the ether, receive no ACK, and then wash their han

I'm not sure I buy that example; if it's a time-sensitive issue, Co-worker can't just fire something off into the ether, receive no ACK, and then wash their hands of it. That's a deeply broken process. If they don't hear back from you in scenario 2, they should find someone else. If they absolutely need you then there should be some way they can escalate to a higher-priority channel (phone probably). (And I certainly hope you have an "on-call" status of some kind.)