BitAsset markets can die slowly, never gain adoption, or suffer a black swan. In these events delegates would like to stop publishing feeds but this would prevent margin calls and new shorts from setting a price. In theory if delegates permanently stopped publishing feeds then the value of the BitAsset = BitAssetCollateral/BitAssetSupply "on average" and it comes down to game theory on shorts/longs settling voluntarily.
However, there is still the situation where some BitAsset holdouts refuse to sell (potentially lost their keys) which means that there are some Shorts that are unable to buy and then cover to free their collateral.
In the interest of having a robust system that can handle all of these situations gracefully I would like to propose that with delegate approval (majority vote) a BitAsset can be "reset" and all longs/shorts have their positions closed at the price feed. Some protections can be put in place such as requiring a 2 week waiting period during which delegates can be voted out before the close out becomes official.
With this in place the result of a blackswan would be all BitUSD is converted to BTS funded by the collateral at a price that allows all shorts to fully cover.
This will protect the BitAsset markets at all stages in their life cycle and allow the network to continue without hardforks.