-While not a bug per se, the for of the output should definitely be
-improved. Not clear how.
+The MD5 hashing is not satisfactory. It is computed for a file only if
+the said file has to be read fully for a comparison (i.e. two files
+match and we have to read them completely).
+
+Hence, in practice lot of partial MD5s are computed, which costs a lot
+of cpu and is useless. This often hurts more than it helps, hence it
+is off by default. The only case when it should really be useful is
+when you have plenty of different files of same size, and lot of
+similar ones, which does not happen often.
+
+Forcing the files to be read fully so that the MD5s are properly
+computed is not okay neither, since it would fully read certain files,
+even if we will never need their MD5s.
+
+.SH "WISH LIST"
+
+The format of the output should definitely be improved. Not clear how.
+
+Their could be some fancy option to link two instances of the command
+running on different machines to reduce network disk accesses. Again,
+this may not help much, for the reason given above.