... could someone explain what is happening, and why?

Its easier to start from the beginning :) you've got too much code in the question, trim it down to absolute minimum, use Data::Dump::dd for generating sample input, and for verifying the encoding of data, deal with just 3 strings, input, wanted output, actual output, and explain what you don't like about actual output

I don't see no problems here, or need to encode/decode anything myself (perlunitut: Unicode in Perl) since libxml knows about encodings 

#!/usr/bin/perl --
use warnings; use strict;
use XML::LibXML;
my $orig = "<?xml version='1.0' encoding=\"ISO-8859-1\" standalone=\"y
+es\"?><tag string=\"s&#195;&#188;&#195;&#159;e\" />";
my $dom = XML::LibXML->new(qw/ recover 2 /)->load_xml(  string => $ori
+g );
dd( $orig );
dd( "$dom" );
dd( $dom->findvalue( q{//*/@string } ) );
printf "%v02x\n", $dom->findvalue( q{//*/@string } );
dd( map { ord $_ } split //, $dom->findvalue( q{//*/@string } ) );
__END__
"<?xml version='1.0' encoding=\"ISO-8859-1\" standalone=\"yes\"?><tag 
+string=\"s&#195;&#188;&#195;&#159;e\" />"
"<?xml version=\"1.0\" encoding=\"ISO-8859-1\" standalone=\"yes\"?>\n<
+tag string=\"s\xC3\xBC\xC3\x9Fe\"/>\n"
"s\xC3\xBC\xC3\x9Fe"
73.c3.bc.c3.9f.65
(115, 195, 188, 195, 159, 101)

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In reply to Re: Encode double encoding? by Anonymous Monk
in thread Encode double encoding? by DrkShadow

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