Gestalt's it's own thing, I think. Unless the shift moves selectively, shifting parts at different rates, stopping halfway would leave all parts halfway. Gestalt on the other hand is the, well, a gestalt of human and wolf - a collection of parts of creatures that creates a creature that is greater than the sum of its parts.
Utilizes the parts that make wolf great, and the parts that make man great to create a form better than either. In theory, anyways.
Half-way would leave you with some funky s***. Half-human half-wolf head, chest somewhere between flat and barrel, leggish arms....
Yeah, not pretty...
