Not sure if the Brits had stayed out of the war, when a german victory was in sight... a german hegemony was not in British interests.
However, Germany asked, prayed and threatened Belgium to allow german troop movement until a few minutes before the attack to prevent a violation of Belgium neutrality and so hoping that Britain would stay out of the war. A few hours or days before the decleration of war, the Kaiser even thought about a change of strategy - defense in the west, all in in the east against Russia. Although his railway-experts thought it to be possible, High Command did not have the nerves to change the plan so short before execution.
In hindsight, it would have been worth the risk. Austria-Hungary could have avoided the early defeat of Przemysl and therefore be a stronger partner in the east...
However, Feldmarschall Larry will be in Paris in 40 days or so

Onward to victory!