Sure there is, by its velocity. If you allow those with lots of money to control a significant portion of its velocity, they can control its value.
I did not say that people (rich even) cannot affect value of Bitcoin. But you're concentrating on aspects of influence which do not have any particular significance. Since all money must always be in a possession of someone, it is useless to select an arbitrary group of those possessors and ascribe them some power other than that of possession of Bitcoins.
Assuming the actual supply is stable, slow velocity will always cause deflation, high velocity will always cause inflation.
This is the quantity theory of money. It's also not necessarily true.
You aren't seeing the big picture, I'm afraid. The bitcoin speculators are probably already wealthy. The panic/crash scenario would work differently as it is currently a side currency, but if the stock market were denominated in bitcoins, the wealthy would stand to make a great deal. I'm not talking about the value of BTC crashing; on the contrary, it would rise assuming it was widely accepted.
But this makes even less sense. If the value of Bitcoins rises, all the holders of Bitcoin become wealthier. In the extreme, the "bad guys" would end up having all the Bitcoins, and all the prior owners of Bitcoin would have the wealth (in dollars, goods, company shares, etc.). Then Bitcoin will become impossible to transact (since the "bad guys" won't sell) so people will start a new blockchain. I fail to see how this is either a problem or beneficial for the "bad guys". It sounds like a really silly plan.
I don't know where this legal tender argument has spawned from, but it is simply flat out wrong. Is gold legal tender?
Your argument here was that "the bad guys" can manipulate the laws (e.g. to create a central bank) by fabricating a panic, not that they can affect the price. Your objection makes no sense.
Just because it is or isn't legal tender does not mean that lots of people can't lose money by the commodity being manipulated.
All value of everything changes all the time. Being rich merely increases your range of options. It does not make you able to predict the future more accurately.
He is stating that money can't be neutral in the sense that inflation and deflation don't exist as a function of money itself either.
He said that the labels "inflation" and "deflation" are not economic terms. Economists can talk about increase/decrease of the quantity of money, or increase/decrease of exchange-value of money.
You say potato, I say Milton Friedman.
Well Friedman advocated central banking.
The problem isn't who holds the wealth, but who holds the guns.