I cannot imagine how it could actually be implemented. Discussions tend to drift off in a variety of directions rather spontaneously, and I doubt that most users would do the work to make sure the interface and subgroups actually stayed useful.
Perhaps an alternative would be to allow the reader to collapse threads or expand threads (as in one of our older platforms).
I am finding that many of the very discussions get to be very long and cumbersome to navigate if I find myself interested in reading or responding. This, I think, is largely due to the spawning of subtopics and discussions that are related to the original post but not necessarily a response to it as its own entity. I am wondering if it would be valuable to some to have subtopics within the thread so that folks who want to create one could do so without leaving a particular discussion. This could allow a singular point to be discussed without creating so much clutter and chaos. A person could bounce between the individual discussions without leaving the main topic. This would require another button, I suppose. Something like "Create/Join related discussion". Thanks.

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