You left out the best part from the doc ;-)

"This surprising autovivification in what does not at first--or even second--glance appear to be an lvalue context may be fixed in a future release." (empasis added)

I think the hash key gets a value of "", can't see how that is good...

Most of my hashes are balanced. By that I mean that I always fill all branches, but don't always define a leaf.

So, this example seems to be a work around...at least for my purpose:

use strict;
my $self = {};
my $f1   = "aaa";
my $f2   = "bbb";
my $f3   = "CCC";
my $val  = "val1";

# Create another valid branch
$self->{$f1}{$f2}{DDD} = 'val2';

# Looking to test for:   $self->{$f1}{$f2}{$f3} = val1 
# But DON'T want to create anything if it isn't created

print "pre count = ".%$self."\n";
print "found\n"  if (defined $self->{$f1} && defined $self->{$f1}{$f2}
+ && defined $self->{$f1}{$f2}{$f3});
print "post count = ".%$self."\n";
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