I'm on a roll today, here's another question:
How come when I put these into
.inputrc, they both do the same thing?
TAB: menu-complete Shift-TAB: menu-complete-reverse
i.e. they both do whatever the last one says.
Readline doesn't know anything about a modifier called
To bind an action to Shift+Tab, you need to find out what escape sequence your terminal sends. In bash, run