Does rank 6 mean you can use it only if your 6th level char (even if you can learn it earlier)? Also Tashi is taijutsu genius nin and Rekka Koha is ninjutsu technique but it uses swordplay (so it can be considered a hybrid jutsu which could benefit either genius nin). But then again his true red eyes triggered by his bloodlust could have boosted up his chakra and talent for one shot use of technique which otherwise he could not had never used :P. So kinda anime power boost push this case (unintentional one though).<br/><br/>Oh well, hopefully this goes as interesting story flow instead that I got accidental hax going on :P.