As taught by our English language teacher back home who are not native speakers, we learn that "too...to do" contains the negative implication which means the opposite to the face meaning, as in "he is too young to visit adult sites= he is not old enough to do so."
While the above example is very simple and easy to understand, the following one is a little longer and much harder:
"The plan offered to our deliberations affects too many particular interests, innovates upon too many local institutions, not to involve in its discussion a variety of objects foreign to its merits, and of views, passions and prejudices little favorable to the discovery of truth."
From "The Federalist Papers" by Alexander Hamilton and his forefathers
And I notice there is a "not" before "to", that means, it is a double negative? The plan is complicated enough so we must do what? Perhaps the sentence is too long to be understood.