"When" to use Limit Break seems to be mostly situational. For example if you have a caster or range Damage Dealer in a group its best to use Limit break right at the beginning of the boss or as soon as it is available in a boss fight due to how long it takes for it to build up..... which is total bs to begin with. Of course this will also depend on where you are in the dungeon. If on the last boss just use it when you feel its the best time... like if certain adds spawn in the middle of the boss fight like in AV...ect. I hate how slow Limit Break builds up when a caster or range damage dealer is in the group... there is no reason for it.

Anyway for healers or tanks its best to use Limit Break when all hell breaks lose and Death is knocking on the door.....

Again Limit Break is very situational and every person will have there own opinion on it... Some people are "glass half full" and will shrug it off. Some are the "glass half empty" and will complain and cry about it. I'm the kinda person who would see the glass of water and wonder why the room is slowly filling up with water.... anyway to each there own.... would it hurt to have a limit break tutorial? it could possibly hurt to have a tutorial or it could be a good thing... It will come down to how much depth the tutorial has. Best bet is to have at least 3 different situations for each role and make sure to say that Limit Break is situational and should not be used on a trash mobs that are in between boss fights unless the situation calls for it.... which proves my point that Limit Break is situational.