* inotify_add_watch internally uses a single watch per directory, which
  may be shared by multiple clients (using filenotify.el).  The problem
  here seems to be that these clients may use different FLAGS as
  argument to file-notify-add-watch.  Currently, the last added client's
  FLAGS become the effective mask for the underlying C-descriptor,
  meaning that clients added before may not receive change or
  attribute-change events if the mask was modified accordingly.

* It seems to me that the right word here is "unified".