If I disable Alt+f from being menu access then any Alt+f keypress should be passed to the application.

To reproduce:
1) Open gnome-terminal.
1.5) Ensure a bash shell is available.
2) Disable menu access keys.
3) Type "foo bar" and place the cursor at the start at foo using the arrow keys.
4) Type Alt+f

The cursor should skip to the end of the word "foo".  However an 'f' character appears at the start spelling "ffoo bar" on the command line.

This effects any libreadline using programs as Alt+f is a common shortcut in readline.  It also effects the mighty, mighty emacs when used in the terminal.