Well done.
I saw most everything coming, but I like that that was a feature rather than a bug in this case. The structuring of the story around a discussion of tragedy in literature was an especially interesting device, especially in regards to "tragedy" and "comedy" in a Shakespearian play meaning something very different from how the words are used in common vernacular today. In particular I like how, after his death, it mentions that if Mr. Hill had been there to argue he would've argued that his own death was not a tragedy, because of course he would continue his education of his students on concepts on literature, even whilst dead.
I'm glad the story explicitly worked with MacBeth, because that is the primary tragedy I think of when I think of a tragedy based around obsession.
I also like that in this particular case Mr. Hill goes into his own tragedy with eyes open. He chooses the tragic ending because to choose otherwise would be worse. No one in the story knows he's a hero, but he's a damned hero, and the reason this story IS a proper tragedy, even in the literature sense, is that he has proven himself noble through his actions, even if he is not of noble birth in the classical sense. He saw a way to save a life that no one else would believe, that no one else will thank him for, that no one in his own narrative will consider him a hero for, and he said "dammit, I'm going to do it anyway, because it would be wrong not to."
The only small quibble I have is that, since he knew the exact date of his death, and the manner, it seems like he could've avoided it by just staying home, or having the car crushed into a cube at a wrecker, or just simply not driving faster. But I think that's beside the point. Perhaps this series of events could only have ever happened with someone who would choose to take this ending for himself. Or perhaps his avoidance of the day would've just caused an even more unlikely series of events to occur, someone else driving a similar car on the same road, and so maybe by driving faster then he saved a stranger's life at that point.