It seems that the link to part 2 is broken. Here is a working link: https://medium.com/slack-design/threads-in-slack-a-long-design-journey-1c9b1af652c9 https://

It seems that the link to part 2 is broken. Here is a working link: https://medium.com/slack-design/threads-in-slack-a-long-design-journey-1c9b1af652c9 https://medium.com/slack-design/threads-in-slack-a-long-desi... In their testing, it does not seem like they prototyped an N-nested (indented) threading model like on Reddit or HN. I am not surprised that it would be hard to understand how all the replies fit together without such nesting.