Hornla makes sense
The Schlieffen plan was logistically impressive but impossible (despite the Entente worst efforts) and almost certainly diplomatic suicide. Any POD that trashes that 'plan' does Imperial Germany one huge favour.
As bad as the Slieffen plan is, the Germans stick with it because the alternatives are even worse-
First, there is no evidence whatsoever to support the contention that Belgium is the cause for British intervention. Grey, Churchill and the rest of the liberal interventionists as well as the Tories are concerned only with British security and that demands backing Russia and France.
Only a direct act of aggression by the French and the Russians might be enough to upset that calculation
Second, the Schefflien plan does largely succeed in its prime objective- the removal of the French threat. While France remains in the field, her heavy industry is lost and her army crippled. It buys time to deal with Russia
It also pushes the French far from the German border Any respectable penetration of the Rhineland will bring an end to the German war effort in a matter of months. The iron mines, just 15 kilometers from the border, provide 85% of her iron ore. Without them, she is done in six months at most
Third, any strategy that allows the Russians to complete their mobilization will be fatal. An attack East is not going to produce decisive results. Russia can easily afford to lose Poland- which is the best that can be accomplished.
Fourth, the early German advances in the East aren't much to write home about. The logistical issues alone pretty much doom the effort. Its not until spring with the Gorlice-Tarnow offensive that any progress is made. Even that is unlikely without the heavy Russian losses in the various East Prussian offensives