The way I understand CH's "color code" right now--
Thread that is new To ME--
title is bold
Thread I have read completely--
title is Not Bold, and the background bar behind the title is gray
Thread I have read, that has posts I have Not read:
title is bold, small blue dot to the left of the title
There may be a few other combinations I'm overlooking.
So, here are two suggestions that are NOT based upon the individual reader that indicate When a thread was Created--
1) when a post was Created 24 months ago, the title is Not Bold; thus all "fairly current" posts retain a bold title. Posts that are old, Even If I Have Not Read Them and Even If They Have A Very Recent Reply, do not have bold titles
2) when a post was Created Within the last 24 months, the title bar background is a new colour-- say, light blue since the site already uses blue as an indicator color? Thus all "fairly current" posts retain a bold title and have a visual cue that they are "fairly current." Posts that are old, If I Have Not Read Them and Even If They Have A Very Recent Reply, have white backgrounds.
Perhaps, also, CH would like to change my suggested 24 month range to a much narrower 6 months, so last years' NYD CNY Easter July 4 etc threads would not be revived as the date approaches this year.
One HUGE advantage of this approach would be that mobile users would know about the age of a thread. Currently, when on a mobile platform, the Creation Date is not displayed.
Thanks for listening. I know ~I~ resurrect something about posting on oldddddd threads every year or so... and I'd say I accidentally bring a 4 year old, 6 year old, ancient thread to the top with a comment about once a month.