It seems the author is flat-out telling us that Harry is deliberately acting irrational, and commends him for it. Curious.

The math does add up, though: Quirrell is at least four times more important than all of Azkaban put together. It's like how, in my mind, at least 10% of the loss caused by the 16-40k guillotine deaths in the French Revolution is from the early death of Lavoisier.

It's pretty clear from the times it's come up that Harry's utilitarianism is either mistaken or too unnatural to actually guide his behavior- and so this just seems like more evidence of that.