Yeah. There's also suspicious comments made by Lakshmi in regards to the Warrior of Light's soul being 'Stained'. Which may or may not imply that the Warrior of Light is Tempered. Especially since 'Stained' is, I believe, the rough translation of Tempering in the Japanese localisation. Add to that recent knowledge of an actual cure for Tempering combined with the frequent display of various degrees of Tempering severity then I don't believe it to be a farfetched theory in the slightest.
Furthermore, even if the Warrior of Light is not Tempered at present then that doesn't mean that it won't be a possible threat in the future, especially if Hydaelyn tries to compel the Warrior of Light to do something that he does not want to do. Which could involve something entirely well meaning but sinister - such as a second Sundering or attempting to compel the Warrior of Light to serve as the new heart of Hydaelyn.