<p>Actually, we were always on topic. The whole idea the chidori boosts speed( at least why I originally thought it did) was predicated on the fact that kakashi experienced tunnel vision while running with the jutsu. The fact that there is tunnel vision would imply that kakashi is running at a speed such that his optic-nervous system cannot properly process the visual stimuli in his peripheral vision, which is why he could not see the sword that was about to chop his arm off. The visual information is literally not being processed in time, which is the whole reason why raiton armor (neurotransmission speed increases) and the sharigan( precognition/visual acuity boost) offers a solution to those running at extreme speeds. Since I also used to think that ninja always run at their top speed in battle, it was a no brainer that the tunnel vision must have been caused by a speed increase offered by chidori.
The whole reason the obito vs minato was brought up was because I was proving that Minato WAS NOT using his top running speed in that battle, for the same reason he told kakashi to not use a technique that requires him to run so fast. When Minato uses his top speed, obito knows it and so do the readers. Context is important.
</p><p>But then, that right there is the problem. The ninja verifiably aren't always using their top speed in battle. Sasuke had to train to rock lee levels of speed as stated in preparation for his usage of chidori. Rock lee understood that running in a straight line with maximum acceleration the way sasuke would induce tunnel vision. The use of one's top speed in battle is situational, because using their top speed comes with risks: Tunnel vision, being unable to change direction as fast as you normally would, leaving yourself open counter-attacks, and also, as shown with KCM naruto, he initially could not even control his shunshin speed because his foot got stuck in the ground and yamato had to help him. Gaara himself has access to his sand body flicker which we have seen him use before, yet he often stands in one spot while he is fighting and relies purely on his defense. A casual relook at the entire manga with an open mind shows that the characters aren't going at their absolute fastest 24/7, even in high stakes battles.
</p><p>Hell, the only reason sasuke and lee are using small bursts of high speed constantly is because of the nature of gaara's defense and fighting style. Gaara is a stationary opponent and the sand shield blocks their attacks, so in order to outmanuever the sand guard they need to run circles until they find an opening. We never see rock lee fighting anyone else like that. Rewatch his fight with kimimaro for example. He only used his top weightless speed once to get behind kimimaro, and even then kimimaro reacted to it with his bone technique. In other instances, the body flicker technique is only used to retreat from battle or chase after fleeing opponents, or when the character needs to use his top speed to avoid an extremely fast attack or protect comrades from an attack that is about to kill them. Only rarely do we see characters using the body flicker technique offensively in battle, and when they do it, it's normally to close the distance and catch the opponent off guard, and then the fight switches to combat speed anyways...
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So with that out of the way, it makes perfect, and logical sense, that chidori does not boost the speed of the user it simply requires the user to be moving at high speeds if they want to use it optimally as it is a piercing move, as moving at your highest speeds induces tunnel vision without the appropriate reflex boosts. And yes, kakashi uses lightning blade because of his personality. Even in the situation against deva pain when pain stabbed him with the rod, kakashi should have used rasengan there because it doesn't require hand seals, and he is literally in close quarters combat with Pain. Don't forget, kakashi made the raikiri because he failed to make a rasenraikiri by adding his chakra nature to rasengan, and the raikiri is literally the only technique he created himself. Everything else he copied. I think it's a pride thing.
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