I understand the concept, but HN has never worked that way, and if it did the results would be so bad that I believe (though I realize it won't convince you) that even you would recoil in horror. It would also kill HN pretty quickly in all the ways we care about, though I suppose the numbers would go up.
Take, for example, any Apple product announcement. The front page is filled with "Apple Open Sources Swift" articles from 100 different sources before things settle down. I can remember when I first started reading through HN and it didn't seem like anyone was performing that job... so they took hours or days to go away. Now we have only one thread within minutes.
If the stories had really been the same we would have merged the threads and left a "comments moved to..." post in the other one. But I was worried that the delta was a bit too great to deprive those comments of their original context. That particular dilemma doesn't come up all that often, which is good because we don't have a good solution to it.
