The actual translation is not "don't fry the eggs" it would be something more like "during the frying of the eggs". As said before it means "all in all", "at the end of the day", "when it comes down to it", "when the chips are down", "in the moment of truth", "when push comes to shove" etc. ( From: http://forum.wordreference.com/showthread.php?t=2262330&langid=6 )