I ask you when a swordman in one piece fights does he turn off his haki ?
What skill has the next WSS has learned since joining the SHs?
Can you bring any skill training panel after joining?
From what I remember the upcoming new WSS is training his body , learning and improving his haki( mihawk only teach him haki)and improving his weaponry.
With your logic of "skill" only Zoro has been wasting his time.
You think the final fight with be without haki or something?
Get a brain dude.