While I don't address everything you said with a quote, I do believe almost all your points are covered somewhere in my post.
First, the red text:
This reveals that the George Lucas' work on "a system of levels" is used by (and presumably for) Nick Gillard for the purpose of gauging the competence of combatants.
George Lucas has stated that there are two separate Star Wars universes:
This viewpoint is recognized by Lucas Licensing, which handles the Expanded Universe:
There's two things to take from this. One of which I already stated, the second is that the Expanded Universe is subjective (i.e. foggy mirror).
Now, here's the best part: within the context of the Expanded Universe continuity, levels were established to organize continuity within Lucas Licensing.
You're familiar with them, and also probably familiar with the quote I'm about to show you, but perhaps you need a refresher:
Man! So George Lucas' unpublished notes are the highest level of authority within the same continuity of Exar Kun's amulet blasts?
(please log in to view the image)
Which then leads us into the blue text:
Anakin Skywalker is stated to be a tier nine in George Lucas' tier system. Published or not, it doesn't matter, it's G-Canon.
So, let's outline what we have here:
Both within George Lucas' absolute continuity, and the Expanded Universe's subjective continuity, Anakin is a level nine swordsman.
That's fact. That's law. That's that.
--- --- --- --- --- --- --- --- ---
Now, with that established, let's address some points!
This argument made my physically cringe when I read it. Rather than arguing for the sheer incompetence of Nick Gillard, let me propose you with the likely alternative: George Lucas never designed a set scale in the first place. It's not of George's nature to always set-in-stone something like that. Simply look at this video: https://www.youtube.com/watch?v=Dvi_qx-2j1Q&t=1m17s. This isn't Lucas being incompetent either, it's that just details aren't relevant to conveying the point. It doesn't matter to Lucas what scale is used for lightsaber combat. Frankly, what very well might have happened is Lucas simply used different scales during different meetings with Nick Gillard - perhaps even within the very same meaning. However, the main idea is still expressed. Regardless of what scale is being used, there is incredible consistency with the tiers: Anakin still ends up the same level; Obi-Wan still ends up the same level. So yeah, this is a completely minor point to me, and it should be for you too.
Except why are you expecting lightsaber duelists to be static? They're not. Some lightsaber duelists can't be constrained to a simple level. Indeed, Anakin is alongside Sidious, Yoda, and Mace - he is in their tier, is he not? That does not preclude Anakin from being, in certain situations, greater than them, however. Again, consider Mace varies between an eight and a nine, yet he is also listed alongside Sidious and Yoda, who do not. There is no contradiction in this quote.
This... just isn't true. We know it isn't true since we know they're created to gauge how skilled combatants are. Yes, of course it doesn't factor in context to specific situations, but it's mighty useful for forum debating, is it not? In regards to Anakin and Obi-Wan, again, refer to Sasukedc's post. Sasukedc goes through the Revenge of the Sith novelization (line-edited by George Lucas, mind you), in which it explains Anakin was significantly handicapped in his fight vs Obi-Wan due to a variety of factors that would not come into play on a neutral battlefield. So, indeed, if there is a list of factors for a fight, it might not be that important. If it's standard mindset in an empty environment, like almost all versus fights are, it's very important.