- Resets the index to match the tree recorded by the named commit,
- and updates the files that are different between the named commit
- and the current commit in the working tree.
+ Resets the index and updates the files in the working tree that are
+ different between <commit> and HEAD, but keeps those which are
+ different between the index and working tree (i.e. which have changes
+ which have not been added).
+ If a file that is different between <commit> and the index has unstaged
+ changes, reset is aborted.
++
+In other words, --merge does something like a 'git read-tree -u -m <commit>',
+but carries forward unmerged index entries.