How many Warrior of Light exist in story?

[BillyKaplan]

there'd be no reason not to bring, say, Thancred or Y'shtola, right?

Other than the fact that the game seems to acknowledge you bring allies along for the sole reason that this is an MMORPG and most content you are forced to run in groups. If you truly acknowledge that other individuals were present, the story falls apart as so many others are rubbed of credit they rightly deserve as they fought alongside you. IIRC, Thordan doesn't look up at you and your comrades and marvels at your collective strength, you alone are present for him to fear.

As for the rest of what I said, yes, tempering would've been inevitable, but there're more than enough examples present to show that just because someone faced off against a Primal does not necessarily mean they have the Echo. That would sadly tie in with canonically yes acknowledging your nameless teammates - they're "acceptable losses", compared to any named NPC.

[Anonymoose]

If you truly acknowledge that other individuals were present, the story falls apart as so many others are rubbed of credit they rightly deserve as they fought alongside you. IIRC, Thordan doesn't look up at you and your comrades and marvels at your collective strength, you alone are present for him to fear.

Only if you acknowledge some quests referring to your allies to mean that your allies are present for every quest, no? Neither the Duty Finder nor the quest journal claim that the Singularity Reactor was attended by any more than you (not even when the Minstrel embellishes it.) While it's true that due to game mechanics you travel with friends into every instance, is there something inconsistent with the black and white line between alone and not alone being to accept what the game tells you? Contrast the Singularity Reactor to something like the Steps of Faith, where it specifies your allies.