Hello ateague,
You had the right answer from Loops, i want to add only few words about your last question: "Is there a way to conditionally split target elements off into separate files and duplicate elements "outside" the target element to separate files without having to read the input file multiple times?" Even without a good module to multiplex the output you have no need to re-read the file. You can just build your custom print sub: 
sub print_dup {
    
    foreach my $fh ( @previously_opened_handle_for_write ) { print {$f
+h} @_ }
}

[download]

You can also review similar question here at perlmonks as this one or my naive approch

HtH
L*
There are no rules, there are no thumbs..
Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.

In reply to Re: XML::Twig - Filtering and duplexing output to multiple output files by Discipulus
in thread [SOLVED] XML::Twig - Filtering and duplexing output to multiple output files by ateague

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