From Cracked.com: 9 cooking myths you probably believe. How many did you believe?
I would add this about searing:
If I am cooking a good steak, I will basically only sear it, and eat it rare. You can do your searing at the end to get the extra browning and flavor if you are making a roast. If I am braising/stewing/slow cooking something, I still sear it to get the flavors - the cooking juices will keep it moist, and you can't brown the meat when you're done if you're making something like pulled pork or beef stew.