I think this would be of extremely limited use, and since the 'if' command already has this capability, it's fairly unnecessary. I think a significant improvement over the current situation would be to allow multi-line command strings (delimited by '\'), and that would be very easy to implement. It would also be easy to implement an optional 'else' keyword that's just ignored, along with an 'else if' that starts a new 'if' command.

If you really want the 'switch' syntax, I might suggest using a very simple preprocessor to build your keys file from a more readable version.