+--aggressive::
+ Usually a three-way merge by `git-read-tree` resolves
+ the merge for really trivial cases and leaves other
+ cases unresolved in the index, so that Porcelains can
+ implement different merge policies. This flag makes the
+ command to resolve a few more cases internally:
++
+* when one side removes a path and the other side leaves the path
+ unmodified. The resolution is to remove that path.
+* when both sides remove a path. The resolution is to remove that path.
+* when both sides adds a path identically. The resolution
+ is to add that path.
+