I changed the title of the topic to be more explicit, so please correct it if I got the gist wrong. While we could do this, there are a lot of different reasons an observation’s updated_at date might change, not all of which imply a need for more IDs. For example, adding an annotation changes updated_at, so does just editing the obs to change the description, as well as DQA votes, adding to a traditional projects, and any number of background tasks.
How about we add it as an option and not the default and see if it’s useful?
I should also note that “clearing the backlog” of Needs ID observations isn’t exactly a reasonable goal in my personal opinion. Many observations can’t be ID’d and will probably sit in Needs ID forever, or until the state of our knowledge changes (e.g. we discover that red palps on jumping spiders in County X always means species Y). I think we should all be doing our bit, and I think reviewing everything in within particular search parameters is laudable, but actually having nothing in Needs ID is a bit lofty.