Actually there are two sets of command map entries for switching/toggling between a pane dialog and the current MDI window. There are also commands to switch between the current Tool or Navigation pane and the current MDI window.
The Toggle Output command as well as the other Toggle (pane) commands by default will open the specified pane and then toggle between it and the current MDI window. If the !ViewDlgToggle global is set to 3, the behaviour changes to opening and closing the pane dialog.
Usually the !ViewDlgToggle global is setup in the Config\Startup.cfg file by adding the following line to it.
GInt !ViewDlgToggle 3
The View Tool Pane (Shift+Esc) and View Navigation Pane (Ctrk+Shift+A) commands do the same but for the whole pane and not just the dialogs within the pane.
The other set of commands have the same behaviour as the default Toggle (pane) commands but are not effected by the !ViewDlgToggle global and thus only switch between the pane dialog and the current MDI window. Some of these commands are View Output, Find List 0, Find List 1.