This is a nice blocking scheme on an inside zone play where the two TEs execute an assignment swtich.
On a normal inside zone blocking scheme, this might be the blocking assignment as the covered TE (red) blocks the DE lined up across from him, and the uncovered TE (yellow) moves to the second level. But this is a very difficult block for the red TE because he has to reach to his inside to gain leverage on a much bigger defensive player.
The solution is to swap assignments. If what shown below is done, the block on the DE is much easier for a TE as he already has the positioning advantage. Then the red TE pulls through to go to the second level.
The yellow TE is already in position and all he has to do is not get over run. This reduces the amount of footwork that has to be done had the blocking assignment in the first picture been done.
+6 yards. Not a huge gain, but I like how the two TEs work their side of the formation.