Faris does have the best total stats of anyone in FFV. And if we're talking about specifically the Chicken Knife, then she's also the strongest attacker, because the Chicken Knife uses both Strength and Agility to calculate damage. As I understand it, this is -supposed- to be true for other knives and bows and suchlike, but a bug in the damage formula causes the game to pretty much ignore your Agility stat. Since the Chicken Knife uses a unique damage formula, it doesn't run into that bug.
However, a quick FAQ check tells me that Faris is -not- the only character to get bonuses to all stats, Lenna/Reina and Bartz do too. I would conclude that the person you were quoting was not in possession of all the facts.
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I don't like this duchy. Now, it's an adventurer.