The Mind Palace technique did not have these limitations.
The Mind Palace technique relied on conscious associations rather than subconscious associations. The imagined location that served as the mind palace was the association between memories and thought. It made the mind palace a mental databank and database of sorts that hosted all kinds of information that could very systematically be accessed.
The Mind Palace technique made the user's mind closer to that of a computer!
It was exactly what Rui needed.
The training regime focused on largely ensuring the mind palace that the user imagined inside their minds was absolutely perfect. There could be absolutely no room for ambiguity, vagueness, imprecision and inconsistency. The user had to be able to quickly imagine it in high-definition, and it had to exactly the same each time otherwise the technique simply wouldn't work.