In Normandy, American infantry units did not do a good job of overwatching from their own hedgerow as they attacked the next, Gen. DePuy explains:
You see, one of our training deficiencies was that almost all suppression was done by indirect fire weapons. Very little suppression was done by small arms. Occasionally, we would use our heavy machine guns. People thought first about mortars and artillery, then heavy machine guns, and finally, light machine guns. Really, they didn’t think much about using riflemen for suppression. They just thought of using riflemen for maneuvering and sharpshooting. The M-1 rifle was a precision weapon but there were no precision targets. This problem was not confined to the 90th Division. You have read SLAM Marshall and know that even in the 101st only 25 percent of the troopers fired.* And, we only had eight heavy machine guns in a battalion. So, it didn’t work very well. We didn’t do direct fire suppression very well in my outfit until the latter part of the war.