I had this realization recently and I'm sure that I am not the first one to realise this, but there certainly are similarities between the Don't You Ever Leave jam (played after Throw Away Your Television live from 2003-2007) and the song Save the Population. The chord progression F-G-A is played in both the strumming part in the beginning of DYEL and the part of STP when AK sings stay all night to save the population. Another similarity are the descending vocal lines Please don't you ever leave and stay all night to save the population, again the same notes. In 2006 they played a part of STP in the DYEL jam in Berlin, which is just another indicator. It's also important to note that they started playing Don't You Ever Leave right after the Greatest Hits Sessions when they wrote Save the Population.
What do you think? Is this only a coincidence and we still have hope for a full Don't You Ever Leave song or is it clearly evolved from Save the Population?