why would it be omittable in the single-argument (and possibly others) case, but not in all cases?

Again - I've only skimmed A12 so I am probably wrong :-) However, consider:

bar $foo, 1;

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Does this mean:

($foo.bar), 1

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or:

$foo.bar( 1 );

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The colon disambiguates it:

bar $foo: 1 == $foo.bar( 1 );
bar $foo, 1 == ($foo.bar), 1;

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In reply to Re^7: Get rid of the Indirect Syntax, please! by adrianh
in thread On the Improvement of Exegesis 12 by Anonymous Monk

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