Think about it, a router routes the edge of the board. Usually the PCB manufacturer adds two holes of their own choosing to align the board. Now the router can make one pass along the outside edge and your done.
This layout is a mess because of the notches in the boards. If there were no notches, the the cutter could cut them apart with no waste, but the cutter has a width to it.
You can't cut these boards apart in one pass so you have to separate (v-score) and route separately.
They MAY be able to do the boards with the notches removed.
That's why a lot of board manufacturer's only want one design per artwork.
I'm speaking from a machinist's point of view.
"v-scoring" is basically cutting in the shape of a "V" not all the way through so the pieces can be broken apart.
There is another way, but I have no idea how to do it. It's where the pieces stay attached in places. The end user breaks them apart.
e.g The boards are attached via 3/16" bridges, say 2-3" apart, and you receive them uncut in those areas.
They "could" score the boards in those areas so they break rather nicely, but you can't break an "L-shaped" section.