I think the trick to reproducing it is to start the process and then wait for a lot of new posts to come in on the feed while you are view the other content and that’s what throws things off, almost like DAMUS is recording where you are from the beginning of the feed, but the beginning changes while you are viewing a profile. so if you just take and try to do it really quickly it always seems to work cleanly.

This seems to be really bad at 7:00 am when I am on the bus because there are lots of new posts coming in. Bad at 5:00 pm as well. Must be the two largest posting times.