Bound the alternatives claim to one read, and point the grammar at it

CHANGELOG.md

@@ -18,9 +18,9 @@ replacement, and each removed path, column or flag.
   `parent`, a name repeating inside one parent row, a name spelling another row's key, a table named like a column of any
   table above it, a table whose format or cell references its own family, and,
   within one render and draw group, a path drawing a table another path selects a
-  row of, or two paths pinning different rows of one table. A read inside a cell is
-  weighed against another only where both rows can render together, which two rows of
-  one table, or rows under two different rows of an ancestor a path pinned, never can.
+  row of, or two paths pinning different rows of one table. Two cells are weighed
+  against each other only where they can render together: not two rows of one table, and
+  not rows under different rows of a table a path pinned.
 - `New` refuses a root choice of templates sharing one format and one set of string
   fields, naming the rows TSV to write instead.
 - `misc.territory`, `misc.currency`, `misc.language`, `misc.httpstatus` and