No...he saw Yona helping the fire tribe and did the same - even if it was to please her. If Yona never bothered helping the firetribe Tae Jun would never have bothered changing. Yona's actions = Tae Jun changed.
Anyone without an inherent bias can see that Tae-Jun was swayed because of Yona's actions. In fact a very small minority in my opinion think it was ONLY because he was in love with her. Discrediting Yona again and again is not cool imo. But to each their own.
I'm not denying that Yona changed Tae-jun. In fact, I outright wrote it. But she didn't
sway him. She didn't have to actively search him out, convince him to listen to her. He was sulking for 3 months, thinking about nothing but her. She didn't have to win him over, only direct him. There's a difference.
And implying that there're people out there who don't have an inherent bias is, honestly, quite amusing. People who perhaps don't have an inherent bias about this manga are those who never heard of it. Also resorting to
ad persona pretty much speaks the weakness of your arguments, since the moment you try to discredit your interlocutor is the moment you show you don't know how to disprove their arguments.
Why should the author reveal everything from the start? Kashi must not be some made-up character that came out of thin air because Kusa was thinking of ideas. I am sure she planned this whole thing and this character from long before. Why would the lady be mentioned in the fire tribe arc when women don't have much significance in royal matters in Kouka?
I'm not saying that everything must be revealed. But if this is as planned as you presume it is, then all the more reason to foreshadow it early. Bah, Yona's mother was mentioned at the very beginning. So was Su-won's mother, and she didn't even appear personally to this point. Why wouldn't Iguni be mentioned? Or not even mentioned, it would be enough if she was simply shown in the background, maybe biding farewell to her husband. How can you be so sure this character was planned, if there was no sign of her for, what, 158 chapters? Not certain, but 150 at least. She screams of nothing but a very recent addition to the story to me.
If something was planned from the beginning, it was Yona learning that her father was an incompetent ruler - that was foreshadowed as early as the first few chapters of the manga, with Hak overhearing complaining soldiers in a flashback. Fire rebellion was planned - it was foreshadowed by Su-won's comments during his coronation. Perhaps a full-out war between Kouka and Kai is foreshadowed, with prophecy an' all. But Lady Convenient Iguni came out of nowhere. This is precisely a sign of an unplanned addition. So are the last two arcs, which are structurally off (especially the Xing Arc), but I could write an essay on that. If anything, it appears that with the end of the Water Tribe Arc - followed by the sudden drop in quality - we entered an uncharted territory and the mangaka herself has only a vague idea of what she wants to happen next.
