Google defines pithy as "(of language or style) terse and vigorously expressive."
However from the meaning of pith with respect to fruits, the word doesn't seem to contain the attribute of being terse. i.e. when describing a sentence or exposition as pithy I would be figuratively saying it contains a lot of pith/meat.
So I'm wondering if being terse or succinct is a connotation of pithy, or is it not necessary. Can a long sentence or exposition that has substance be called pithy?