I'm pretty sure I accidentally did the opposite of this tonight. I picked up a "tri tip" from the store. I noticed that it didn't have grains running in different directions, but I just assumed that it was a part of a tri tip. Did the reverse sear, got it to about 130 degrees and then sliced across the grain. After cutting and tasting it I believe that I bought a piece of a brisket flat that was mis labeled as tri tip. It was tough and nothing like the tri tips I have cooked before. Now I know you can cook a tri tip like a brisket, but cooking a piece of brisket like a tri tip is not advised.