They also both guarantee direct hits for the corresponding actions that involve collecting 3 Sen… Am I missing something here though that happens behind-the-scenes, because the action description for Tsubame-gaeshi still says “Repeats the previously executed iaijustu with increased potency” despite not actually raising the potency. Is there some hidden buff that happens behind-the-scenes, or has the action description been wrong for a long time?
In fact, the only real difference between the two sets of actions appears to be that one set involves GCD attacks while the other set involves oGCD ones, which is underwhelming.