I bought a prime 14# brisket at Sams that yielded 4 # meat. I usually get 7#....I guess I got an unlucky odd brisket?...Thoughts please..

A few details: Ys640s.  14 hr cook.. Paper wrapped at 5 hrs 160 degrees...Entire cook 225 to 250 degrees.  Done at 198 degrees. Tender. Juicy...Just not enough .

1st say I believe you.  That seems unusually heavy loss.  Even if it was a 14lb. untrimmed brisket I would only think you would have about 3lbs in fat.  Say another 45% in cooking loss and you are still at 6lbs.  I have no idea how it could happen, unless the weight on the package was wrong!

I hadn't thought of the incorrect weight possibility. I bet that's it.