The first castaway to "successfully" play the HII was Yauman in Fiji.
What made Yauman's play memorable is he did it on a hunch that he might be at risk of being voted out. The ones who were trying to blindside him kept it quiet right up to the end only to have Yauman turn the tables on them when he played his idol.
Others played the HII also to save themselves (Amanda in Skankivor: Micronesia comes to mind) but she was flat out told by all that her name was going to be written down at TC. So playing her HII at TC was as big a no-brainer as you're going to get.
And when you consider all the castaways who did play their HII and ended up not needing to after the votes were tallied, it makes Yauman's feat even more impressive.