Mary,

Maybe I can give you a simpler (but incomplete) explanation:

The added weight of the wings is more or less offset by the reinforcements to the beam that will be necessary to widen the boat, so the wing's weight is not the big issue.

The main diference between increasing a given boat's width and adding wings to achieve the same total width lies in the contribution to righting moment from the leeward hull.

When you add wings, this contribution remains unchanged, but it grows when you increase the distance between the hulls.

The other main contribution to righting moment - crew weight times distance to centerline - remains the same in both cases.

As a consequence, the "wide" boat will have greater lateral stability then the "winged" boat - it will stay upright with more sail area or with more wind using the same sailplan.

Diagonal stability is also different, but this is another story.

Cheers,