@{$_[0]}     # easy --- deference an array reference
[  @{$_[0]} ]    # ok --- turn it back into an array ref.. why?
@{ [ @{$_[0]} ] } # umm -- uh.... well, the @sign implies
                             # we have an array, but how is it 
                             # different from the first array we
                             # dereferenced?