I found that with my Avatar and having Beast, Ifan and Sebille in party, from late Act3 (Reaper's Coast) onwards, I can have the same conversation multiple times with each henchman.
Meaning that if I click to talk to one of them, I can go through the dialogue options which are supposed to be once-only, but after finishing that tree, (sometimes even before clicking the character again), that same option exists again for selection as if I had not had the chat earlier.
It really became noticeable on Lady Vengeance after Reaper's Coast and during Council of Seven / Nameless Isle where it started affecting all 3 henchmen for every dialogue option rather than sporadically during Reaper's Coast.
