It happened to us in the real world. And was fixed in 9.2
It has happened to us too, though it was very easily fixed in our case due to the excellent deadlock reporting. And I can also confirm that the case for Joel (the original reporter) is also a real world case.
Link to talk about it http://www.pgcon.org/2012/schedule/events/483.en.html
Edit: Not sure if I would call it braindead though. Highly annoying, yes. Alvaro has spent a lot of time into solving this, it is much harder than it initially seems.