Originally posted by ILS
I think the general understanding is that Luke needs to be in tier 10 otherwise it would be vacant, and moving anyone else up to tier 10 would destroy the structure of the rankings, because part of what the tier is based on is Yoda, Sidious, Windu and Anakin being tier 9s as duelists, as per Gillard.
Whoever said a tier 10 was needed?
Not really. One just needs to look at their comparative showings against Katarn and Gaalan respectively to see how comparable their skills are, their own battle against one another pretty nicely solidifies the idea.
In terms of lightsaber ability, Caedus and Luke are definitely on the same tier. Luke consistently one-ups him via superior power in the Force, though.