Don't let Moltke loose his nerves and keep this one army corps he sent to the east
(can't remember it's name and number, but in any case it came to late to assist in the battle of Tannenberg it was intended for)
and place it between the 1st and the 2nd corps, where the BEF and 5th french army came through, causing the german retreat in 1914.
Maybe another possibility :
Let them skip the original Schlieffenplan (HERESY

) and let the germans go with an early Ludendorff plan, he adviced - or at least worked out as a "homework" put to the archives as it WAS rendered heresy by his then superiors - after he assesed roads and railways in Luxemburg, Ardennes and western France : an early idea of "Sichelschnitt" (read it in a biography I can't find atm).
But an early german victory I think is a good bet to keep the "old order" hang around for some time.