Rageblade question.

So I get that it...

GUINSOO'S RAGE's attack counter and empowered effect both occur on-attack, not on-hit. The item will not interact with abilities that apply on-hit effects (e.g. Bladesurge Bladesurge, Mystic Shot Mystic Shot, Infinite Duress Infinite Duress). UNIQUE – GUINSOO'S RAGE: Every other basic attack will trigger on-hit effects an additional time.

But how come it doesn't apply or seem to apply to Xin Zhaos three talon strike? I remembered back then when Feral Flare did effect it and made his Q only have to hit twice to knock up. (Strat. ruined lol)