Edited sentence: According to the directives of Plan XVII, the French mobilized and hurled their forces towards the German border, in an ill-fated attempt to recapture the Alsace-Lorraine, which very nearly cost them the war.However, Moltke's subsequential weakening of the German right, the uncalled for obstinacy of the defense of German territory against the French attacking forces and the transfer of three army corps and one cavalry division from the western front to help contain the Russian advance into East Prussia destroyed the essence of the original plan, and led to the inability of the German army to break through the Allied forces at the Marne.In essence, Schlieffen's audacious plan was never carried out - it was destroyed by Moltke's indecisive policy.It can be argued that had the original concept been followed, the German Army would have attained a swift and decisive victory.This played exactly into Schlieffen's conception of a trap through double envelopment, which called for a loose defense of the border, and actually for retreats by which the French forces would have been lured further away from the main thrust of the German advance.Though speculations are essentially not a part of historical investigation, this idea is bolstered when one takes in consideration the French Army's movements early in the war.With the benefit of hindsight, there is strong evidence to assume that it would have been very successful