send_messages return value via return_message_id enhancements

[nicholasserra]

If I send three messages, but one of the messages doesn't have a recipient, then at this stage the pm_messages list will have only two elements.

How is user-code supposed to figure out which of the three messages didn't get send? That is, after this point, there's no difference between:

connection.send_messages([wrong_message, correct_message1, correct_message2])
connection.send_messages([correct_message1, wrong_message, correct_message2])
connection.send_messages([correct_message1, correct_message2, wrong_message])
Would be great if the return value could then be

[None, message_id1, message_id2]
[message_id1, None, message_id2]
[message_id1, message_id2, None]
in these cases?