Tom - okay Barnbougle is no 10 in your mind, how about PacDuns? Many many people out there would have no problem adding one or both of these world gems to their personal "10"s - me included.
I know some very well traveled raters who refuse to give ANY course a "10" arguing "if I do so I'm setting the bar for perfection." Always leaves me scratching my head... "so you've played St Andrews, PVGC, CPC, Merion, NGLA, Melbourne, etc etc and refuse to recognize any of them as tens???" Seems like that only introduces a bias into the resultant averages.
You too? Can you, in your own mind, build a ten?
J