Easier way would be working a deal with bitstamp for a USD credit line collateraliced in BTC. You can even use some multisig addresses to hold the collateral, removing some trust issues. When you need more USD in bitstamp, you can send more BTC to the address. When BTC raises, your collateral becomes more valuable, and your credit gets better.
But on a crashing market you'll need to have a lot of BTC on hold to refill the collateral, or that could end on a disaster...