I think I have already spoken enough on the subject. You will undoubtedly note that my opinion has not fluctuated, regardless of the short-term price swings (including the current one).
The Taylor series expansion is an approximation, which is plenty accurate in a majority of contexts. That said, it's, obviously, an approximation.
There's quite a bit of literature on the specific aspects of the accuracy of this methodology.
1) Zomma, eh? No, dgammadvol isn't directly related to skew, AFAIK. It assumes a parallel vol shift.
2) No, AFAIK.
EDIT: Obviously, I could very well be wrong about these.
Thank you for the compliment... And yes, indeed, the problem is that money and debt doesn't ever exist in a vacuum. It's almost always more about the politics than economics.
That's not correct... In general, kings routinely enjoyed the benefits offered by fractional reserve banking and only had issues with it when the bankers refused to cooperate (e.g. Edward I of England and the Ricciardi of Lucca in the 13th century). The point is that, if you're the king...
Firstly, the description of fractional reserve banking as high treason is rather misleading and wrong. Secondly, there is no record of Josiah Stamp ever saying anything like what's quoted above.
Why shouldn't they charge us interest on it? Banking is a business. If you wanna borrow money from a bank, why should it lend this money to you for free?
Maybe if we were living under strict sharia law, with its prohibition of riba...
The US political economy, given its current structure, creates this optical debt. In a way, you can think of it as the whole world lending the US money to be its policeman, fight its wars, etc etc.