Good concern. You can use the following ETF currencies to help see how the dollar is doing. The only good thing is when the dollar drops the price of oil goes up. UDN & FXE looks like dollar started to weaken a month ago - about 8% now
You are hedged against the currency issue via being invested in oil. The value of a barrel of oil is constant across currencies. If the dollar tanks against the Franc, the value of a barrel of oil (in dollars) will skyrocket.