The USD's most important risk factor are tapering concerns.
If QE remains then you should see BTC going back up with a weaker dollar.
Also vice versa, lower bitcoins with more faith in the dollar.
Start thinking about the bigger picture when you want to play cryptocurrencies.
If the Eurozone of US show signs of weakness in their currency, albeit anything really -- btc's value will go up.
A good way to keep track of US dollar's trend is by looking at the Dollar Index vs. 6 major currencies.
You are making a very big assumption... That Bitcoin itself can be considered stable ground with a stable value that will reflect in changing price as fiat currencies are debased.

That's a pretty large leap of faith.
(The word on gold is that an ounce of gold has always been about the right price for a gentleman's suit. You could dress up for it in Ancient Rome, and you can dress up for the same amount of gold in XXI. century New York. It's not entirely exact, but mostly it stands true. That's why you can speculate with gold against money supply - even though irregularities happen, like what happened in the last few years. However, Bitcoin has no agreed upon value. Over the last few years, a Bitcoin could buy anything from a can of Coke to a used car.)