columns. It may be useful to simplify/merge some of the properties and
use footnotes for more detailed explanation.]
-Key:
-++ major advantage
-+ minor advantage
-- minor disadvantage
--- major disadvantage
---- showstopper
-
-+------------------------------------------------+-----------------------+
-| Design Property | Designs Proposed |
-+================================================+===+===+===+===+===+===+
-| **advantages** | 1 | 2 | 3 | 4 | 5 | 6 |
-+------------------------------------------------+---+---+---+---+---+---+
-| Compatible with garbage collection |\+ |\+ |\+ |\+ |\+ |\+ |
-+------------------------------------------------+---+---+---+---+---+---+
-| Does not break old clients |\+ |\+ |\+ |\+ |\+ |\+ |
-+------------------------------------------------+---+---+---+---+---+---+
-| Allows direct sharing | | | |\+ |\+ |\+ |
-+------------------------------------------------+---+---+---+---+---+---+
-| Efficient use of bandwidth |\+ | |\+ | |\+ | |
-+------------------------------------------------+---+---+---+---+---+---+
-| No repeated changes |\+ |\+ |\+ | | |\+ |
-+------------------------------------------------+---+---+---+---+---+---+
-| **disadvantages** | 1 | 2 | 3 | 4 | 5 | 6 |
-+------------------------------------------------+---+---+---+---+---+---+
-| Can result in large DMDs |\- | | | | | |
-+------------------------------------------------+---+---+---+---+---+---+
-| Must traverse immutable directory structure | | |\- | |\- | |
-+------------------------------------------------+---+---+---+---+---+---+
-| Must traverse mutable directory structure | |\- | |\- | | |
-+------------------------------------------------+---+---+---+---+---+---+
-| Must suppress duplicate representation changes | | | |\- |\- | |
-+------------------------------------------------+---+---+---+---+---+---+
-| "Out of sync" problem | | | |\- |\- | |
-+------------------------------------------------+---+---+---+---+---+---+
-| Unsolved design problems | | | | | |\- |
-+------------------------------------------------+---+---+---+---+---+---+
++---------------------------+
+| Key |
++======+====================+
+|\+\+ | major advantage |
++------+--------------------+
+|\+ | minor advantage |
++------+--------------------+
+|\- | minor disadvantage |
++------+--------------------+
+|\-\- | major disadvantage |
++------+--------------------+
+|\-\-\-| showstopper |
++------+--------------------+
+
++------------------------------------------------+-----------------------------------------+
+| Design Property | Designs Proposed |
++================================================+======+======+======+======+======+======+
+| **advantages** | 1 | 2 | 3 | 4 | 5 | 6 |
++------------------------------------------------+------+------+------+------+------+------+
+| Compatible with garbage collection |\+ |\+ |\+ |\+ |\+ |\+ |
++------------------------------------------------+------+------+------+------+------+------+
+| Does not break old clients |\+ |\+ |\+ |\+ |\+ |\+ |
++------------------------------------------------+------+------+------+------+------+------+
+| Allows direct sharing | | | |\+\+ |\+\+ |\+\+ |
++------------------------------------------------+------+------+------+------+------+------+
+| Efficient use of bandwidth |\+ | |\+ | |\+ | |
++------------------------------------------------+------+------+------+------+------+------+
+| No repeated changes |\+ |\+ |\+ | | |\+ |
++------------------------------------------------+------+------+------+------+------+------+
+| **disadvantages** | 1 | 2 | 3 | 4 | 5 | 6 |
++------------------------------------------------+------+------+------+------+------+------+
+| Can result in large DMDs |\- | | | | | |
++------------------------------------------------+------+------+------+------+------+------+
+| Must traverse immutable directory structure | | |\- | |\- | |
++------------------------------------------------+------+------+------+------+------+------+
+| Must traverse mutable directory structure | |\- | |\- | | |
++------------------------------------------------+------+------+------+------+------+------+
+| Must suppress duplicate representation changes | | | |\- |\- | |
++------------------------------------------------+------+------+------+------+------+------+
+| "Out of sync" problem | | | |\- |\- | |
++------------------------------------------------+------+------+------+------+------+------+
+| Unsolved design problems | | | | | |\-\-\-|
++------------------------------------------------+------+------+------+------+------+------+
123456+: All designs have the property that a recursive add-lease