Braising brisket internal temperature
After 6-8 hours at 225° your meat's going to be 225°, there's no value of measuring its temperature. After a couple of hours any piece of meat will reach the same temperature of the oven. When cooking tough cuts like brisket target temperature is immaterial, you're never going to serve them less than well done, the point is to cook them long enough for the connective tissue to break down into gelatin. 

Measuring temperature is important when roasting tender cuts and you want a particular doneness level.