IMHO the C- hold only causes the nipple to point up if you use more thumb
pressure.  The C hold can allow the nipple to protrude straight out if
the pressure is applied evenly, you can also make the nipple point
downward by applying more pressure to the bottom of the breast.  I do
think that the scissors hold almost automatically produces some breast
compression if you are taking a firm hold on the breast.  The scissors
hold is much less supportive of a large breast than the C- hold as well.
All this probably means that under varying circumstances they can both work.

Sarah Friend Barnett   LLLL, IBCLC
Bronx (New York City), NY  -  [log in to unmask]
" You are not obliged to finish the task,
 neither are you free to neglect it."       R. Tarfon