A few points
Hat and Cloak almost slipped and said time travel.
Mary sue time travel is a common device in fan fiction.
The author has stated MoR includes elements that are necessary to ensure artistic completeness as a work of fan fiction.
Mary sue time travel was derisively referred to in the same conversation in which the idea of Sirius Black conspiracy theories were debunked.
There is a person in Azkaban who endlessly repeats “I’m not serious” (Sirius).
It is not possible to travel more than 6 hours back in time with a time turner.
Prophecies transmit information further back in time than 6 hours.
Atlantis was erased from time.
The Weasley twins remark that the Marauder’s Map is showing errors.
The Sorting Hat still works.
From the above, I suspect that Mr. Hat and Cloak is a time traveler who has an earlier version running around in the present.
A few points
Hat and Cloak almost slipped and said time travel.
Mary sue time travel is a common device in fan fiction.
The author has stated MoR includes elements that are necessary to ensure artistic completeness as a work of fan fiction.
Mary sue time travel was derisively referred to in the same conversation in which the idea of Sirius Black conspiracy theories were debunked.
There is a person in Azkaban who endlessly repeats “I’m not serious” (Sirius).
It is not possible to travel more than 6 hours back in time with a time turner.
Prophecies transmit information further back in time than 6 hours.
Atlantis was erased from time.
The Weasley twins remark that the Marauder’s Map is showing errors.
The Sorting Hat still works.
From the above, I suspect that Mr. Hat and Cloak is a time traveler who has an earlier version running around in the present.