State-free protocols are useful when the server side is distributed and potentially disconnected. :-)
As for "wonderful heisenbugs" -- the AWS services return a clear "hey, your clock is broken" error, so it wouldn't be very hard to developers to figure out what was going on.
As for "wonderful heisenbugs" -- the AWS services return a clear "hey, your clock is broken" error, so it wouldn't be very hard to developers to figure out what was going on.