Clever, though it's worth noting that ping times circa 1812 tended to be measured in weeks or months. Mail was likely already three weeks old when delivered, urgency generally low. That said, reading two-week-old (or older!) news often has a similar effect --- much of the urgency or uncertainty has been resolved.
by the nineteenth century in the UK most mail across the country would be delivered the next day. (im not sure of the history, it could be that in 1812, things were kind of slow, but it quickly sped up!)
A decade or so later into the Victorian age, mail sent in the same city was to be delivered within a couple of hours. In London there there twelve deliveries a day and in smaller cities up to about 6 times a day. People were able to reply and get responses in one day.