Under (at least) 5.6.1 it enables you to say:

@a = qw/foo bar/; 
print @a->[1];
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And see 'bar' as a consequence rather than insisting upon:

print $a[1];
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print @a[1];
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results in: Scalar value @a[1] better written as $a[1].

Interestingly, in Perl 6 @a[1] will be valid again since the convention that the leading sigil should indicate return value as opposed to the type of thingy you're accessing is confusing. I take it that this arrow syntax was an attempt to bridge the two approaches, but I didn't even know about it til you brought it up :^)