为何SYSTEM用户可以将V$SESSION的查询权限赋权给其他用户而SYS用户却不可以？

现象如下，难道SYSTEM比SYS用户的权限更大吗？

SYS@ora11g > grant select on v$session to lhr;
grant select on v$session to lhr
                *
ERROR at line 1:
ORA-02030: can only select from fixed tables/views
SYS@ora11g > conn system/lhr
Connected.
SYSTEM@ora11g > grant select on v$session to lhr;
Grant succeeded.

GRANT SELECT ON SYS.V_$SESSION TO SYSTEM WITH GRANT OPTION;

SYS@ora11g > col OWNER format a10
SYS@ora11g > col object_name format a15
SYS@ora11g > SELECT d.owner,d.object_name,d.object_type FROM Dba_Objects d WHERE d.object_name IN  ( 'V$SESSION','V_$SESSION');
OWNER      OBJECT_NAME     OBJECT_TYPE
---------- --------------- -------------------
SYS        V_$SESSION      VIEW
PUBLIC     V$SESSION       SYNONYM
SYS@ora11g > SELECT d.owner,d.synonym_name,d.table_owner,d.table_name FROM DBA_SYNONYMS D WHERE D.synonym_name IN  ( 'V$SESSION','V_$SESSION');
OWNER      SYNONYM_NAME                   TABLE_OWNER                    TABLE_NAME
---------- ------------------------------ ------------------------------ ------------------------------
PUBLIC     V$SESSION                      SYS                            V_$SESSION
SYS@ora11g > SELECT D.OWNER,
  2         D.NAME,
  3         D.TYPE,
  4         D.REFERENCED_OWNER,
  5         D.REFERENCED_NAME,
  6         D.REFERENCED_TYPE
  7    FROM DBA_DEPENDENCIES D
  8   WHERE D.NAME IN ('V$SESSION', 'V_$SESSION');
OWNER      NAME          TYPE               REFERENCED_OWNER    REFERENCED_NAME   REFERENCED_TYPE
---------- ------------- ------------------ ------------------- ----------------- ------------------
PUBLIC     V$SESSION     SYNONYM            SYS                 V_$SESSION        VIEW
SYS        V_$SESSION    VIEW               SYS                 V$SESSION         VIEW
SYS@ora11g > SYS@ora11g > SELECT * FROM V$FIXED_TABLE d WHERE d.NAME IN ( 'V$SESSION','V_$SESSION','GV$SESSION');
NAME                            OBJECT_ID TYPE   TABLE_NUM
------------------------------ ---------- ----- ----------
GV$SESSION                     4294951258 VIEW       65537
V$SESSION                      4294950919 VIEW       65537
SYS@ora11g >