The 1st SS Panzer Division's Dash Westward, and Operation Greif
Operation Greif (German: Unternehmen Greif; meaning "Griffin") was a special false flag operation commanded by Waffen-SS commando Otto Skorzeny during the Battle of the Bulge. The operation was the brainchild of Adolf Hitler, and its purpose was to capture one or more of the bridges over the Meuse river before they could be destroyed. German soldiers, wearing captured British and US Army uniforms and using captured Allied vehicles, were to cause confusion in the rear of the Allied lines. A lack of vehicles, uniforms, and equipment limited the operation and it never achieved its original aim of securing the Meuse bridges.
(An aside - the halftrack in the background is a Hanomag, which plays a prominent part in Snow Sticks.)
The dry description outlines the operation but fails to tell about the distrust and confusion sown by the German imposters. Once the word got out, "real" Americans and Brits asked all sorts of questions along the lines of "who won the last world series" when a suspected imposter was encountered. Unfortunately, many of the imposters knew the correct answers and sent the Americans off in the wrong directions.
Many of the captured imposters were tried and executed. On the battlefield, many Germans caught wearing US uniforms simply because they found a pair of good boots suffered at the hands of angry GIs. I suspect that many imposters were shot out of hand on the battlefield: GI justice.
After the war, several of the captured imposters escaped the death penalty when the various Allied clandestine operators testified that they had operated in enemy uniform.
The "good" guys in SNOW STICKS and ONE STICK AND A WACO were treading on ice the many times they masqueraded in German uniforms. The Gestapo had no reservations at all. The only delay before execution was for torture and interrogation.
For more on Otto Skorzeny and Operation Greif.