Update doc/contributing/erm-guidelines.md

Author: jasnell

doc/contributing/erm-guidelines.md

@@ -85,7 +85,8 @@ So with this is mind, it is necessary to outline some guidelines for disposers:
    the object should be disposed as if an exception had occurred. For instance,
    if the object API exposes both a `close()` method and an `abort()` method,
    the disposal method should call `abort()` if the object is not already
-   closed.
+   closed. If there is no difference in disposing in success or exception contexts,
+   then separate disposal methods are unnecessary.
 1. Disposers may throw their own exceptions but this is not recommended.
    If a disposer throws an exception while there is another pending
    exception, then both exceptions will be wrapped in a `SupressedError`