Interestingly, what he actually said (that we've since simplified to the more pithy misquote you've given) was, “No plan of operations extends with certainty beyond the first encounter with the enemy's main strength.”
It was his way of explaining why plans need what we today call "branches and sequels." Options. If this, then that kinds of options.
Today, some folks interpret the shorter version as advice against planning at all. "Wing it," is what some conclude. But that's not what von Moltke meant at all.
Go Vols!
p.s. Will anyone other than OMG know what BPBOTWHBSA means? Will OMG?