Server Administration :: Unused Columns

If you mark a column unused, is there any way to project it? I know the docs say you can't, but as the data is still there I would have thought it should be possible. I can see the column in dba_tab_cols, but the obvious ways of making it usable don't work:

orcl> select column_name,hidden_column from user_tab_cols where table_name='DEPT';

COLUMN_NAME HID
------------------------------ ---
LOC NO
DNAME NO
DEPTNO NO

orcl> alter table dept set unused column loc;

Table altered.

orcl> select column_name,hidden_column from user_tab_cols where table_name='DEPT';

COLUMN_NAME HID
------------------------------ ---
SYS_C00003_13071316:19:02$ YES
DNAME NO
DEPTNO NO

orcl> select "SYS_C00003_13071316:19:02$" from dept;
select "SYS_C00003_13071316:19:02$" from dept
*
ERROR at line 1:
ORA-00904: "SYS_C00003_13071316:19:02$": invalid identifier

orcl> alter table dept rename column "SYS_C00003_13071316:19:02$"
2 to loc;
alter table dept rename column "SYS_C00003_13071316:19:02$"
*
ERROR at line 1:ORA-00904: "SYS_C00003_13071316:19:02$": invalid identifier

orcl> alter table dept modify "SYS_C00003_13071316:19:02$"
2 visible;
alter table dept modify "SYS_C00003_13071316:19:02$"
*
ERROR at line 1: ORA-00904: "SYS_C00003_13071316:19:02$": invalid identifier