Hugh M. Cole, The Ardennes: Battle of the Bulge… (1965)
“ A 12th Army Group intelligence summary issued on 12 December echoes the prevailing tone: "It is now certain that attrition is steadily sapping the strength of German forces on the Western Front and that the crust of defenses is thinner, more brittle and more vulnerable than it appears on our G-2 maps or to the troops in the line." This optimism, particularly when heightened by reports that the enemy no longer had fuel for tanks and planes, conditioned all estimates of the enemy's plans and capabilities. It may be phrased this way: the enemy can still do something but he can't do much ”
