Now, I'll stretch my point a little ..... if every aircraft that was lost/uncertain of position went 121.5 / 7700 at the first moment they aren't exactly where they think they are you'd have every training detail and, I suspect a fair number of PPL pilots on frequency within a short space of time.
But I'm not advocating that - go back and read my earlier post re: difference between "unsure of position" and "lost".