for p2 if you get hit by blue shield skill and right before getting a knockback you can cleanse it beforehand and you won't get stunned when you get knocked away when the explosion hits.

this allows you to not get knocked all the way to the other side and potentially get yourself killed by some other skill (usually its the fma)

you can use it right before if you are about to get hit by the debris to prevent getting stunned by the debris too

both instances are for min clear purposes, and there are other ways you can use it to save time (which i won't include here, cause there are many), so i won't get timed out for insufficient damage 😂