G'day Rolf,

"this POD is either confusing or plain wrong"

I'd say a bit of both.

In the context of the first paragraph of "Declaring a Reference to a Variable", experimental::refaliasing should definitely be replaced with experimental::declared_refs.

That section goes on to say, "It is intended mainly for use in assignments to references ...". It would be appropriate to mention experimental::refaliasing at this point.

"NB: that use feature qw(declared_refs) doesn't seem to make sense without the other feature."

There are instances where you want a declaration without assignment (not in "void" context).

I've certainly used "\my VAR" in this context often enough. This doesn't require any special feature or warnings code.

$ perl -E '
    use strict;
    use warnings;
    say ref \my $scalar;
    say ref \my @array;
'
SCALAR
ARRAY
[download]

Off the top of my head, I couldn't think of an application for "my \VAR" in this context; however, just for completeness, here's a contrived example showing that "declared_refs" is required but "refaliasing" is not.

$ perl -E '
    use strict;
    use warnings;
    say ref my \$scalar;
    say ref my \@array;
'
The experimental declared_refs feature is not enabled at -e line 4.

$ perl -E '
    use strict;
    use warnings;
    use feature "declared_refs";
    say ref my \$scalar;
    say ref my \@array;
'
Declaring references is experimental at -e line 5.
Declaring references is experimental at -e line 6.
SCALAR
ARRAY

$ perl -E '
    use strict;
    use warnings;
    use feature "declared_refs";
    no warnings "experimental::declared_refs";
    say ref my \$scalar;
    say ref my \@array;
'
SCALAR
ARRAY
[download]

While these features remain experimental, they're rather unwieldy [see Update below] and probably easy to get wrong:

$ perl -E '
    use strict;
    use warnings;
    use feature qw{refaliasing declared_refs};
    no warnings qw{experimental::refaliasing experimental::declared_re
+fs};
    my ($sc, @ar) = qw{qwert asdfg zxcvb};
    my \$scalar = \$sc;
    my \@array = \@ar;
    say $scalar;
    say "@array";
'
qwert
asdfg zxcvb
[download]

Update: Regarding my comment about experimental features being unwieldy; they are, in fact, not as unwieldy as I presented. I had forgotten about the experimental pragma (thanks to ++ikegami for the reminder). The two lines:

    use feature qw{refaliasing declared_refs};
    no warnings qw{experimental::refaliasing experimental::declared_re
+fs};
[download]

can be reduced to the much simpler one line:

    use experimental qw{refaliasing declared_refs};
[download]