I too was an avid trn user back in the day. I started using "netnews" in Bell Labs back around 1982 and wasted far too much time over the years clicking through the groups that I followed. I seem to recall an earlier 'rn' client, later improved by trn. Trn's ability to kill entire sub-threads was brilliant -- I wish Hacker News had such a thing now. I don't recall just why I stopped participating in usenet. I think my ISP's support for usenet got increasingly weaker and the content was ever noisier.