More Germans shooting each other, but this time it's intentional!
While that has been a plotpoint with Hood, the loss of capitol ships is something Britain can afford for a time. The loss of merchant shipping is far more important, as no ship, plane, soldier, or country can fight without food. Sea Lion's was a half-hearted pipe dream even when it was drawn up, and Hitler's about to invade Russia. If Schreiber is to convince Hitler that oil needed for his panzers are to be diverted to the Kriegsmarine surface fleet, he needs to majorly disrupt the convoys and push Britain to the brink. A full early-war convoy stolen back to Germany is good for the propoganda department, but that's not going to make a significant difference in the tonnage war.