Not sure if your computer's architecture is radically different to mine or something, ...

The first difference I notice is that your fastest iterating solution -- 671/s -- is only half as fast as my fastest iterating solution -- 1100/s.

I seriously doubt my 3 y/o Core2Quad Q6600 @2.4GHz is twice as fast as your hardware.

So the major difference probably comes down to the fact that I couldn't be bothered to install yet another slow-accessor constructor, so I manually code my Person Class:

package Person {
    sub new{ my $p = shift; bless { @_ }, $p }
    sub name{ $_[0]->{name } }
    sub title{ $_[0]->{title} }
}
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After that, why your results should be relatively different to mine I have no idea:

But mine are consistent:

C:\test>date /t & time/t && junk87
24/10/2012
19:39
             Rate    obvious     subtle functional          x
obvious     189/s         --       -16%       -60%       -83%
subtle      226/s        19%         --       -52%       -80%
functional  471/s       149%       109%         --       -57%
x          1101/s       482%       388%       134%         --
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