It was true, but as soon as he arrived in Donauwörth and discovered how badly dispersed his forces were he recognized the Austrian attack on Landshut to be both a threat and an opportunity: his corps could now converge on Archduke Charles from several directions at once.
A student of history, he had many mental models.
As such, he drew upon different strategies.
One must read and dedicate oneself to the craft (or profession) at hand.