3
Ah yes... it's a bummer. Weight is the block order, but the value is for blocks of that particular type. Unless I misunderstood, I tried exactly what you have done and it won't work, so:
Centre - 0
Centre-Left - 1
Centre-Right - 2
Centre - 3
puts Centre - 3 directly under Centre - 0, rather than under the paired left/right blocks.
I would be interested in a workaround for this myself.
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