What works in any individual case is what works. Of course there are
considerations with any job so its dangerous to make broad
One good reason to set the outside first is that it enables you to
properly center the main stone. You can mush it one way or the other
to compensate for slight irregularities in the satellite stone
outline. You can view the alignment of the accents without the
distraction of the center. Also. if you're using a hart bur for the
outsides, you most likely will need the clearance to tip the bur from
the inside, if the center was there it might restrict your movement.
I can visualize this better than I can describe it, sorry.
I don't believe girdles should ever touch but sometimes it happens
because they are maybe not quite the ideal size for the mounting, so
you may have to shoehorn them in. When I was contracting, retailers
would supply stones that were too big and just say, "Oh you can do
it". Well, they're paying and they're supplying so I would do it
their way. I hated it but I did it.
The example you gave with the center set below the sides...how did
that look? Sounds awkward on the face of it, but maybe its a