the point is that you want to localize both the @ARGV array and the *ARGV{IO} filehandle and those are separate actions (that local *ARGV happens to do both of)

The chief state you need to save is the list of filenames (@ARGV)... oh, and the magic filehandle. That is, the two pieces of state information you need to save are @ARGV and the magic filehandle... oh, and, the current file name ($ARGV). Three! The three pieces of state information you need to save are @ARGV, $ARGV, the magic file handle and... Four! Er. Among the chief pieces of state information that need to be preserved are such diverse elements as ...

It's so silly of you to think that I'd do local( *ARGV ) to save just two of the slots!

Perhaps $^I should become an alias for $ARGV{'inplace'} so we can have more controls for how <> behaves, such as making the default for $ARGV{'interp'} be "filenames" not "magical" so <> after echo data > '|echo Perl is my bitch' just reads "data\n" in? Then we'd have even more reason for local(*ARGV) !