Healing in boss battle w/out revita

Hello, guys! This is my first guide in this forum.
I will just pull this out for anyone who have'nt known this and waste alot of revita or even dying in solo. There are several way to recover HP while in boss battle.
Mastering this so you can solo boss without revita?
1) The easiest method(no fighter's high): normal attack boss, then cancel the move right before your weapon hit the boss. It will give you a buff of 200HP twice(it only heal when the the orange HP bar doesn't show up). The buff end if you got hit or you attack.
2) second method(no fighter's high): work best for brawler and swordman: cancel the boss skill - a.k.a flinch. Set shortcut to your best flinch move (hard hit, smash, shield bash...), hit the boss right before it attack to flinch. You will instant HP boost everytime you use it.
3) third method: dodge the boss attack at several time(fighter's high lv1): ask D.Song, I won't quote another people work in my personal post.

*Extra: enable natural recovery in maze: invite 1 member to the party and enter the maze, then tell them to leave the pt. Your HP will start regen like normal.

Here a video of me using method 1 and 2 in battle: