I love thread drift! It's what the real world is like!
It seems like managing it is a limitation in the computer-human interface - if only we could "map" out thread drift visually - like a road map or a flowchart - then a reader could drift with the thread, or navigate just to the posts that connect with solid lines....
(granted this is the only forum I paprticipate inexcept for searching nerdy programmer forums (fora?) for specific issues, and those NEVER have thread drift...)