Re: [CVS] f7, f8 bound..

[Richard Stallman]

    But what's does it mean to delete a key binding?

    Is it the same as adding a keybinding with command = nil,
    effectively removing any binding of the key ?

Yes.

    Or should it restore a default key binding from bindings.el ?

No, that binding is (probably) what you deleted.

    Or is it a combination of the two -  if the current key binding
    is set from custom, deleting means: remove the custom binding and
    restore the default binding; otherwise, remove the default binding.

The first is deleting a customization; the second is adding a
customization to delete a binding.  Those are completely different
operations.