Well, Flash is a magic spell. It runs off the Spell Speed GCD and costs Mana. And more than anything it seems to be the last surviving relic of the 1.0 GLA/PLD that used many succor magicks in combat. I would say it is justified in the ARR side of things by having the conjury subclass experience.
But not every Gladiator ICly has conjury experience. My character Sounsyy is a tried and true Gladiator of the Bloodsands. But she would never ICly use Flash because she has no magical mastery. But I would venture it's perfectly acceptable for a GLA who does boast some magical expertise to use Flash ICly. Depends on a character to character basis I guess.
For Lancer, I (personally) would probably not use anything that seemed magical or dragoon-y. (To be fair though, my lancer characters are all from Ala Mhigo, not Grid or Ishgard.) But Life Surge could easily be played as the Lancers way of tapping into their inner aether and channeling it into a powerful next attack. The rest of their abilities don't seem to aetherially connected. And if you've been receiving training from IC dragoons, maybe you've picked up some of the physical techniques? Whether or not you wanna make fire erupt from your spear is a personal choice.
But not every Gladiator ICly has conjury experience. My character Sounsyy is a tried and true Gladiator of the Bloodsands. But she would never ICly use Flash because she has no magical mastery. But I would venture it's perfectly acceptable for a GLA who does boast some magical expertise to use Flash ICly. Depends on a character to character basis I guess.
For Lancer, I (personally) would probably not use anything that seemed magical or dragoon-y. (To be fair though, my lancer characters are all from Ala Mhigo, not Grid or Ishgard.) But Life Surge could easily be played as the Lancers way of tapping into their inner aether and channeling it into a powerful next attack. The rest of their abilities don't seem to aetherially connected. And if you've been receiving training from IC dragoons, maybe you've picked up some of the physical techniques? Whether or not you wanna make fire erupt from your spear is a personal choice.