If a bad actor tries to manipulate the BitUSD market by dumping on the bitUSD market way below the value of the actual value of the dollar. Then there is an economic incentive for someone to scoop up those cheap bitUSDs, and profit from the inevitable price swing that will incur when the honest actors come in and bring the bitUSD market back it equilibrium with the actual value of the US dollar. The opposite incentive is there if someone tries to pump the value of bitUSD greater than the actual value of a dollar.
As soon as market depth is established, a certain amount of volume is achieved, and skepticism bitassets will work dies down, bitUSD should very closely resemble the value of the US dollar.
Now, I think I understand a bit.
But that raises the next question: why should a bad actor act bad? I assume because he gains something from it, right?
If so, why do honest actors do not act bad? What is their gain?
It works much the same that it does in any free market. Manipulators are taking a risk by manipulating the market. The manipulators are taking a risk that the public recognizes the manipulation and the market immediately corrects, causing the manipulator to lose a considerable amount of money. If they do not recognize this manipulation and see it as a normal market movement, then they stand to profit from it.
You question as to what would someone stand to gain from manipulating the bitUSD market is exactly why I think bitassets will work, because there is really no incentive at all. Unlike Bitcoin being traded in the free market, people can easily look up exactly what the value of the US dollar (or Btcoin, gold, etcetra) is relative to BitsharesX by comparing the current market value of the BitsharesX/USD (or BitsharesX/BTC/USD) trading pairs on other exchanges. It will be much easier to detect manipulation of a bitasset when you know almost exactly what that asset is worth in the real world markets from thing like data aggregators and market feeds which are sourced directly from those markets.
You cannot prevent manipulation in the gold, Bitcoin, Or FIAT markets, but the fact it will be so easy to tell if bitassets do not equal the current value of a real world commodity is the reason why I think it is unlikely to be manipulated. Manipulation will likely be very unprofitable in bitassets due to the obvious value of the commodities traded which people can get from many 3rd party services and data feeds which come directly from those markets. Therefore, bitassets will closely resemble the value of their real world counterparts.