No question about it; makes you wonder what they are chasing. Generally speaking when an update happens you can eventually get the gist of what they were trying to accomplish, a new signal of quality they were enamored with. Last two, no idea what it was. Lots of people saying it was to combat spam, fix canonical problems, put the kibosh on link swapping, but there’s no evidence of that.
Jagger is still a total mystery to me, if anyone has a thought on that, it would be interesting to hear.