[Orgmode] VISIBILITY property and C-u C-u <TAB>

[Gez]

I've just discovered the VISIBILITY property, although I had some trouble 
working out how to apply it .I discovered C-u C-u TAB from reading 
http://thread.gmane.org/gmane.emacs.orgmode/6623.  C-u C-u TAB is documented 
in the reference card but not in the manual or on worg as far as I can see - 
Shouldn't it be added?  Also shouldn't VISIBILITY be listed with the other 
"special properties" in the manual etc?

I'm using it to mark sub-projects (level 2,3 etc) with :VISIBILITY: folded 
(or :VISIBILITY: content when they also contain a sub-sub-project). When 
sub-projects are folded into their projects (level 1) I miss out on an 
overview of all projects.  Using C-u C-u TAB I can see all non-level-1 
headlines that I've marked because they are parents of tasks, and then I can 
visit them locally with TAB.  It's very useful in conjunction with the 
counter cookie, and in column view.

I have a query about the C-u C-u TAB command.  When I've just edited or used 
S-TAB (no matter which part of the global cycle it's on) C-u C-u TAB works 
as I would expect.  But if I've just used TAB, C-u C-u TAB cycles 
hrough  -> CONTENTS -> SHOW ALL etc, even while the mini buffer displays 
"startup visibility plus VISIBILITY properties" at each stage of the cycle. 
C-u C-u TAB also cycles when it's repeated.  I find it hard to keep track of 
whether it will cycle or not while I'm using it to view areas of the 
outline, so in effect, the only way I feel sure I can quickly return to my 
desired startup visibility is with S-TAB C-u C-u TAB, which is a lot of 
keystrokes! So my questions are - is this expected behaviour?  Can it be 
changed?

Gez
Windows XP, GNU Emacs 23.2.1, Org-mode version 7.01trans