These days i've been thinking alot about the Overlay/WN theory, and the Leviathan dlc made me think of something.
In the Overlord DLC, Shep as an organic was pulled into a hybrid Organic/Synthetic overlay, which was being powered by David Archer's mind being put into the Geth consensus. No images were needed from Shep's mind as you could say the reality was always there due to David.
In the Geth Consensus, Shep was pulled into a fully synthetic overlay, to make sure Shep's mind didn't collapse, Legion used various factors from Shep's memories for his brain to understand the new reality, a floor, a ceiling, pathways, reaper code highlighted orange, a gun to remove the reaper code etc.
In Leviathan, Shep is pulled into an organic overlay.
Leviathan's mind control was said not to be perfect and that the Reapers have a perfected form of their "reprogramming/mind control", but what if the Reaper form is also not perfect? I think the Reapers' form is just the synthetic version we call Indoctrination.
I've been thinking Harbinger itself has the perfected form, throughout the games we know that coming into contact with Reaper artifacts and tech can start the process due to the bombardment of electromagnetic, infra and ultrasonic noise and fields.
Leviathan can do this practically instantly if the organic is in range, or through it's orbs if out of range.
From the Leviathan DLC i'm concluding that Harbinger has both the organic version (like the Leviathans) and the Synthetic version (Indoctrination) of this process, due to being the Reaper made from the harvested Leviathans.
When Leviathan took control of Shepard, the only forms it used to interact with Shepard was Bryson and the assistant that shot her father, these people Shepard has only met recently and the environment was Bryson's lab which was only visited recently. It never used any other images, what if it couldn't? what if Leviathan can only access people's short-term memory to work with and control?
In the mining facility, Levi had the reserachers enthralled for 10 years and they just presumably carried on working on their projects, maybe there was something in these projects the Leviathan was very interested in, so got them to carry on working using the thralls' knowledge combined with their own. When new reasearchers came, the Levi's could enthrall these people to find out how far techonology has improved and what recent events have happenned, use this to upgrade facility and research tools, this way new people arriving is a good thing for the facility and Levi's goals.
It never disconnected from them for the 10 years and from the way Levi had them acting around Shepard, one can assume it just needed these thralls' current memories and knowledge, and everything else was supplemented by Levi.
My thinking here is, maybe Harbinger's perfected version can access short and long-term memory and that's what he's using in the final sequence after the white transition, pulling from everything in the environment and whatever can be used in Shep's memories for the sole purpose of Indoctrination.
Levi didn't care about it's thralls' long term memories, as it just needed their bodies, but Harbinger/Reapers prefer their thralls to act independently, just in tune with their doctrine.
The beam run is the only time in the series we get face-to-face with Harbinger, all the other times we heard from from him, he was in dark space using the Synthetic/Reaper form of Indoctrination to carry out it's agenda.
Thoughts?