Anybody not known why very need changing the default Show desktop shortcut from super+d to Super+Ctrl+d keystroke?

[Hammer Attila]

Hy,

If anybody not known, latest Metacity related upgrade changing the 
default desktop show keystroke from super+d to Super+Ctrl+d keystroke, I 
think the changes happened too in Unity environment, so don't surprise.
Look the changelog with new changed keystrokes:
"metacity (1:2.34.1-1ubuntu10) precise; urgency=low

   * debian/metacity-common.gconf-defaults:
     - change the shortcuts as per design request: (LP: #969235)
       Ctrl + Super + D Minimises all windows
       Ctrl + Super + Cursor up Maximises the current window
       Ctrl + Super + Cursor down Restores or minimises current window"

Look following bug to see the entire change history:
https://bugs.launchpad.net/ayatana-design/+bug/969235

Personaly, very new this keystroke me. Oldest time desktop activation 
keystroke in GNOME is CTRL+ALT+D (two hands command). This command are 
used Ubuntu too before Natty. I think Natty this is changed with Super+d 
keystroke, some time this keystroke change very useful for laptops or 
netbooks. For example, I very like this change, because some time fast 
possible press this keystroke with one hand if my other hand have the 
braille display.
Now, this command changed again with Super+CTRL+d command, for example 
my laptop very difficult to press this command with left hand, because 
between super key and CTRL key have the laptop FN key.
If very need change this commands, why not use oldest traditional 
CTRL+ALT style keystrokes?
I don't understand this.

I have got a question:
If I configuring custom keybinding command with show desktop related 
keybinding, future any upgrade will be not owerwriting my custom 
settings again?

Attila