What opportunity did the "Hunterdon Rising" and the subsequent Hessian troop movements create for the Americans? How did Washington take advantage?

The Hunterdon Militia, as it was sometimes called, was a
very decentralized militia in New Jersey, consisting of small bands of volunteer rebels
working outside of Washington's army, in groups as small as three up to whole units of
two hundred or more.

They relied on guerrilla tactics,
attacking Hessian and British patrols only when they were sure they could win, hiding
weapons in easy to reach places and collecting and using them only when an easy target
presented itself.

While these units didn't make a huge
tactical difference in the battles for New Jersey, what they did do was tie down fairly
large numbers of Hessian troops.  Colonel Rall, the Hessian commander, often had to send
50 or 100 soldiers simply to escort a dispatch outside the cities of Trenton or
Princeton, and patrols a short distance outside of town were vulnerable to sniping and
ambushes.  These troops were then not available for the defense of Trenton, while
Washington's army could have relative freedom of movement, and the Hessian/British
intelligence on his whereabouts was limited.

This made it
much easier for Washington to take the initiative and achieve military surprise, the key
to almost all of his New Jersey victories.