For years chefs have told people that searing seals juices into meat. So we toss steak and chops into hot skillets and hot fires in a desire to produce moist results. But in fact searing does no such thing.
The first thing to keep in mind is that cooking meat always results in some loss of moisture (both fat and blood). This is because heat causes the muscle fibers to contract and just like squeezing a sponge. The more heat that's applied the more moisture will be lost. As Harold McGee notes in The Curious Cook (compare prices), if you sear a steak and then turn it over to sear the other side you'll see juices gathering on the top of the steak - a top that has supposedly been sealed by searing. You also see steam and here the steak sizzle if you turn it over again.
McGee did a series of experiments and found that seared meat lost slightly more moisture than unseared meat cooked to the same temperature. He is quick to note that the differences in weight are modest and make be due to variations in the meat and the testing process. But even so, clearly searing did not reduce weight loss from moisture. Shirley Corriher, a biochemist and author of CookWise (compare prices), also debunks the searing myth and notes that food scientists as long ago as the 1930s had proven this idea of sealing in juices is fiction.
And yet trained chefs such as Emeril Lagasse continue to spread this nonsense. They spread the myth mainly because searing does accomplish something - it boosts flavor in a series of chemical changes named the Maillard Reactions. These occur at high temperatures and may increase the glutamate levels in the meat, which we interpret as a savory flavor. So I'm not arguing that you or Emeril should quit putting steaks in a hot skillet or chops on a hot fire because it does make it taste far better. But do it for the taste and not because of a theory long-since debunked.