User blog comment:Kaido King of the Beasts/Chapter 836: Man of a Thousand Pounds/@comment-4374114-20160819181114/@comment-4374114-20160820002330

This is in the same manner in which we first saw Luffy use Gear 3, it was shown off page to break door, and then was fully shown later. For Gear 2 as well, Luffy was able to replicate the ability from watching CP 9 and even they comment how impressive it was that he learned so fast. Currently we don't know how awakening occurs, be it an all at once occurrence or is something that takes a lot of rigourous practice. Even releasing it, it does not mean he has fully control of it, but rather he could be a little overwhelmed trying to keep control. If we are expecting him to fight BM in this arc we should expect this is going to come out.