I just wanted to point out that there is a side effect to not using parens on a subroutine/method call: the called subroutine "inherits" the @_ array of the caller.

Not entirely true. While &foo passes @_, foo and foo() and &foo() do not. Hence, imho for not passing @_ the best solution is to avoid the ampersand where possible (which means you pretty much only use it to create references).

Proof:

sub test {
    print "\@_: @_\n";
}

@_ = qw(a b c);

print 'test; # ';      
test;

print '&test; # ';
&test;

print 'test(); # ';
test();

print '&test(); # ';
&test();

__END__
test; # @_: 
&test; # @_: a b c
test(); # @_: 
&test(); # @_:
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