However, the usefulness of '\local our' in this scenario eludes me. @::data does not get back its previous values.

In that case, as a feature, it still needs work, because it doesn't produce the same results as the existing syntax its intended to simplify:

our @data = 'fred'; 
sub x{ 
    our @data; 
    local *data = shift; 
    print $data[ $_ ] for 0 .. $#data; 
};;

my @junk = reverse 1 .. 10; 
x( \@junk ); 
print ">>@data<<<";;
10
9
8
7
6
5
4
3
2
1
>>fred<<<
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