Keep in mind you're talking about content that is designed not to be challenging, but merely a step in the storyline and leveling content. Limit breaks are designed to provide three scenarios. Mitigate a huge incoming predicatable attack (Ifrit's Inferno/Hellfire/whatever its called) or if you misread the incoming damage heal through it. Or if you're fighting a boss where you need to burst damage to get through a particularly difficult phase.
None of these scenarios are really present early on. Which is why it seems unnecessary because it is. The system is there though so players can get used to seeing it, and play around with it and experiment so that when you're at the end-game content you have a full grasp over what the limit break mechanics are, and then you communicate these to your party members, and use the appropriate skill at the appropriate time to best the encounter. If you're at the end-game and you don't need a limit break at all, then you likely overgear the content and can enjoy your free DPS.
Edited, Jul 1st 2013 9:16pm by desmar