The bilingual sweep had left some blocks with only their last paragraph
translated, a few with the Chinese inserted inside an English sentence,
and some with a repeated paragraph from a re-applied table. A rewrite of
the coverage checks found them; this fixes every block and restores the
comment separators that a cleanup pass had emptied.
Building a topology asks the same geometry question for every pair of
satellites, which is a quadratic number of independent tests, and that loop
is the dominant cost of the construction. The parallel form returns the
same row major matrix in the same order as the sequential one.