[no_flags]

Am I correct in assuming these are mostly to filter out tweets pushed by Twitter from people I don't follow?

[swanson]

Yeah it removes all of the random "liked by someone you follow" or "popular in your network" etc tweets that slowly creep in over time.

[jakub_g]

Yesterday Twitter started showing me "someone you don't follow replied to another person you don't follow" types of conversations and it's gotten really absurd at this point.

[raphael_l]

This happened to me yesterday as well, only it was "liked" instead of "replied". In my confusion I clicked on the account, since I didn't recognize it. Only to mistakenly click the Follow button, as my brain didn't manage to correctly derive the current status of it. Because I actually thought I had accidentally followed them or something similar.