billg
From memory
0= poisonous
1= very basic
2= not offensive but offers very little.
3= average golf course.
4= above average but nothing to distinguish itself
5= well above average, likely to have several distinctive holes. But not worth a special trip.
6= very good course, would be one of the best courses in any area. Play if reasonably closeby.
7= excellent and no obvious weaknesses, eventhough it might not offer anything unique. Play within 100 miles.
8= a course of distinction, worth travelling substantial distances to.
9= a world great, may have one or two weaker holes, but a slew of world great holes too.
10= perfect, don't even miss one hole.
But even Tom Doak doesn't quite stick to this spec. The 10s I'm familiar with all have a hole(s) that you could miss: Ballybunion, Dornoch, St A, Muirfield, maybe even PV.