[@Eklispe] It's a similar thing to how Gloria keeps the gainz from Ship of Theseus even while powered down. A subset of Perception Intrusion showed him the principles required to attack the visual cortex, but after memorizing them by rote, he doesn't need the Arm piloting his actions anymore to do it.

[quote]	● Trackless Step: This technique combines breathing patterns, erratic walking, body posture and specific motions to make the human mind dismiss most of what it sees of Takumi as extraneous information, making it seem to the victim that he teleports or moves lightning-fast, although nothing of the sort actually takes place. This is a technique Takumi developed based on the principles Breakdown showed him, but it is not predicated on him actually using the Arm; it can be taught, if with difficulty.
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