You didn't explicitly deny "RS was involved", but you praised Sanji's haki as the most important factor in him tanking King, and that's where you're wrong.Never denied RS being involve, so Idk where your pushing on, but nothing to debate on if we acknowledge usage of RS. Think your losing point of what we were all discussion early when the talk got started.
Sanji himself admitted it's the RS durability that allowed him to tank such an attack and, prior to the impact, he himself admitted having little faith in being able to tank the attack (and he said so without a calm face). Sanji knew his haki wouldn't allow him to survive unscathed, and King was confident he would tear Sanji in two, but, much to Sanji's surprise (and probably for King, who apparently left him for dead) the RS is more durable than they all expected and it managed to tank the attack to the point we don't see any wound on Sanji's stomach (but we do see it on Sanji's head, which he failed to fully protect with haki from the impact against the ground).
So, to sum it up: Just stop. Sanji has haki, we know he does, but he didn't tank King's attack thanks to his CoA proficiency but thanks to his RS. He used haki as well? Probably, since I doubt he wanted to die, but if haki was the most important factor in stopping the attack, he wouldn't be annoyed at the RS durability nor say anything about it, since it would be a non-factor. This shouldn't even be debatable, coming straight from Sanji's mouth. RS saved him.
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