A breakfront is the oldest solution to the oldest problem in large furniture: how to stop something wide from looking like a wall. Step the middle forward and the eye reads three volumes instead of one plane.
How far forward is not a matter of taste. It is set by the cornice.
The cornice on the wings projects outward from their front face by a certain amount. If the centre section steps forward by less than that projection, the wing cornices run into the side of the centre section before they have finished their own moulding - and the junction becomes a muddle that no amount of carving will rescue. The moulding appears to be swallowed by the piece.
So our master Indian artisans set the break deeper than the cornice projects, always, and then a little deeper again, so there is a clear return of the cornice moulding on each side of the centre. That return is what makes the breakfront read: you see the moulding turn a corner, travel back, and turn again.
The rule is simple to state and it is the difference between three sections and one confused one. Decide the cornice first, then the break.