Has anyone else had trouble with this feature?

I've noticed over the last week that it isn't clicking to the last unread, it is clicking to today.
It just happened again when I clicked on the "This is why we can't stay in our grocery budget" thread. It went to today's comments and skipped yesterday's. The last comment I had read was Coolmom's comment about personal use of a work vehicle and the tax implications. That comment was written on 3/6.

Suggestions? At first I thought it was forgetfulness or distraction on my part, but it is happening fairly often so I don't think it's me.