For the widgets that we show_all() / hide(), on gtkgui init we get an instance of those widgets (the toplevel) and then we use them without parsing the glade file again whereever we need them. In their init we DO NOT show_all(). Of course if we need an entry in a window, we have to parse the glade but only for that entry.

For the widgets that we show_all() / destroy(), we make them from glade visible=False and we implicitly write show_all() in the last life of their init function so we draw the widget after we have finished everything we want to do on it.

use Show_all / Hide
|  use Show_all / Destroy
|  |
x     roster_window 
   x  accounts_window 
   x  account_modification_window 
   x  add_contact_window 
   x  subscription_request_window 
   x  service_discovery_window
   x  agent_registration_window 
   x  preferences_window 
   x  vcard_information_window 
   x  history_window 
   x  groupchat_window 
   x  join_groupchat_window 
   x  tabbed_chat_window 
   x  passphrase_dialog 
   x  choose_gpg_key_dialog 
   x  change_status_message_dialog 
   x  new_message_dialog
   x  add_remove_emoticons_window
   x  groupchat_config_window
   x  remove_account_window
   x  new_version_available_dialog
   x  popup_notification_window
   x  xml_console_window
x     file_transfers_window