Wouldn't people like to buy a book about the lives of Haerta, Ganonron and Jephton?

[B. Dandelion]

2) Nobody is willing to take Redcloak's word in the exact same situation, so "such and such thought such and such off a glance" is being inconsistently applied.

Weren't you the one strenuously arguing Redcloak isn't reliable in that circumstance? I'm inclined to go with his statement.

b) The Dragon mentions she is particularly interested in arcane spells. But interest doesn't let you cast above your caster level, and it's purely imaginative to read from that the conclusion that the Dragon (somehow) managed to add extra casting levels (as many as 4-6 levels!).

So in your opinion, that's just completely meaningless text? Personally I don't see much point to bringing it up specifically unless the intent is to advise people that the dragon is better at spellcasting than other dragons of her age. That's not a stretch at all. "Hey, so-called Ancient Black Dragon appears to have spells a regular ABD shouldn't have. How is that?" See the strip. It's being handwaved.

V is more interested in arcane lore than Xykon, it has no bearing on their caster levels. It might just mean the Dragon spent more time picking her spells carefully (sure seems like it). It doesn't necessarily mean anything!

Okay so you are alleging that. Don't buy it, myself.

On the other hand, the caster level we see is very good evidence

The Giant's made it clear that Plot > Rules and for that matter Funny > Rules so the rules > what's explicitly stated in the text argument is actually not that persuasive.

Especially when you can't even argue the rules bar it, because a perfectly logical out presents itself in the form of the ABD having Sorcerer class levels.

Because she never says that she has extra levels in sorcerer,

Not in so many words, but dude -- that's a perfectly logical inference from her earlier statement. I don't play D&D either and that's what I inferred.

If we see V use Sunburst 3 times in a day we say "yup, V got to 16th level", we don't say "Wow, I guess V got a super ring of Wizardry off panel!"

Unless V had dropped a line about picking up magical equipment off-screen. Then you'd have cause to believe it.

Not to mention, the Giant just might have goofed. He's made it clear on numerous occasion the stats are not mapped out. He doesn't care about being as accurate as possible with regard to rules.