Sadly, the upvote system reacts eagerly to many things that are bad for HN, e.g. indignation, snark, cynicism, sensationalism.
One can speculate about why—my theory is that it plugs into reflexive neural circuits, rather than the slower, reflective ones that make for more thoughtful reactions—but the fact itself is painfully well-established.
Really interesting counterposition of the terms "reflex" and "reflect". Both share the same etymological root and core meaning, but through application have mirrored distinctions that make them perfectly beautiful opposites, in the way you're using them.
It's common for etymological roots to branch to opposites, or simply invert. And then maybe revert again. Almost too common to note, really. A byproduct of how core association is to our minds it would seem.
You theory lends itself to validation. One aspect is timing - upvotes produced later after reading will be more thoughtful. The other aspect is effort - if upvote required certain effort over a length of time, that upvote too would be more meaningful. On the other hand, a short burst of heroic effort points to a reflexive reaction. If we could somehow inject effort into the voting we would get some really meaningful weights for each vote. This could be calibrated with manual review of sample comments. We could also use this knowledge to calm people down - confronting a person with a lengthy task might give them time to rethink their position.
So... how is that for an idea: having voted on something you get an option to return and double-down your vote, but no sooner than five minutes later. To try more things we could also show the user his recent upvotes, and mix in some comments he did not vote on, so that the user had to stop and think.
One can speculate about why—my theory is that it plugs into reflexive neural circuits, rather than the slower, reflective ones that make for more thoughtful reactions—but the fact itself is painfully well-established.