I bet that would lead a lot of people to start using signatures. No thanks.

Perhaps we could assign IDs to posters? The first commenter in a thread is A, the second commenter is B, so that each new thread gives users a new identity.

The problem with that is that anonymity leads to trolling.

Troll posts will be modded down and deleted. That's not really a problem.

It's difficult to have a dialog if you don't know who is the same person and who is someone else. You could do it by assigning a random per thread ID to each participant in a thread.

That would be potentially neat if you were only interested in raw argument. But HN is a place for people to meet as well.

Also, credibility matters. Some people are known for their expertise in certain areas, like Matt Maroon and poker.

That would be a good feature to be able to turn off/on in your site preferences. I would likely leave 'view usernames for comments' off.

Good idea.