Hah. Well it doesn't agree with my intuition either, but note that the handle you're getting from a failed open acts the same as a closed filehandle, which makes some kind of sense:

#!/usr/bin/perl -w
use strict;
open my $fh,'<','does not exists' and die "This file should not exist"
+;
print <$fh>;
close $fh;

open $fh, '<','exists.txt' or die "Not opened: $!\n";
close $fh;
print <$fh>;
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output if 'exists.txt' exists:

readline() on closed filehandle $fh at test.pl line 4.
readline() on closed filehandle $fh at test.pl line 9.
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