The Doctor Cinematic Trailer Theory (How I think it's still canon)
Since The Doctor Cinematic trailer also features Harley waking up as an experiment but with some huge differences then in canon, people assumed that it was just noncanon.
But what if it is canon...just from Harley's perspective?
For Harley labeling Prototype as one of his "Creations" as I've said that l lines up with Harley's implied grandiose disorder as inflating himself as more important then he is.
But, what if these continuity errors are due to Harley's perspective?
First off, despite the differences, Harley says a great deal of lines in the trailer that directly are from "Experiment 1354" tape. So it wasn't like the devs just threw the canon VHS out.
"You have no idea what kind of m-mist-take you just made…"
"You.... B-b-backstabbing traitors!"
These lines, or lines close enough to them, are spoken to Leith and White, despite them being absent from the game.
Speaking of which, the other big difference is that Harley evidently wakes up alone.
But he clearly references other people and the bullying they subjected him to.
Plus the hidden messages and Harley's final speech are all directed at Playtime Co, repeatedly talking about how they thought they could "break" him which indicates a much more hands on torment then throwing his brain in a jar and forgetting about him.
YOU WILL REGRET THIS. THIS WILL NOT STOP ME.
YOU FOOLS THOUGHT YOU COULD STOP ME BUT YOU CANNOT. INFINITY.
"The minds of men are easy to break...you thought you could break mine too..."
But the other big difference is the absence of Leith and Dr. White.
Which is odd as Harley clearly talks to them in the trailer, but at the same time they are nonentities.
I feel like Harley's mind reconstructed the Experiment 1354 memory and this is the result.
Like, Harley insists at the end that he's fine, but the trailer also shows images such as this:
And as I've shown else where the red maze in the ARG emails show he's furthermore his mind is shattered:
For us folks who still remember the humble VHS, There's also a fastforwarding icon at one point as Harley says "backstabbing traitors" in the trailer.
The Doctor Cinematic Trailer is Experiment 1354...but the memory has been rewritten because the raw version is too painful to think about.
Notice how the Trailer version ends on a triumphant note. "I am no man! You thought you could break me, but you were wrong."
Meanwhile in the real version he's screaming in helpless fury while Leiith appears to be enjoying that. "This temper is a baaaaaad look for you, Harley :]" and all that -_-.
Empowering ending (where he blocked out Leith taunting him) vs humiliatingly anticlimactic version (Leith smugly chiding him for his "temper")
By erasing Leith and White, Harley erases the two most painful moments of the memory - since in the original memory, he is composed until Dr. White speaks, and Leith manages to goad him into a rage after he's calmed himself down from hearing Dr. White.