Here is the Brisket. Typically people rest it on the counter or in the cooler then slice. My process (which I got from Kreuz when it was Smittys - Blacks, Taylor Cafe.. all those big legendary brisket houses) rests the brisket for a long time. The fat in between those layers is filled with a bath of three things the meat fibers love to take a bath in, fat, collagen and moisture). A brisket can feel like it has lost all its moisture then pop back.