Not so invisible
Oil prices are low because the Saudis have dumped enormous quantities of cheap oil on the market. Their reason, to undercut the development of North American crude by expensive recovery methods, and to stick it to the Russians and the Iranians who are currently on their shit list. The Russians, especially, are really suffering because of low oil prices. Once they've driven enough US and Canadian firms out of business, and things settle down in Syria, the oil will go back to whatever the market will bear. Its classic monopoly market manipulation: free market capitalism has nothing to do with it.
The only invisible hand I see is the one that's got us by the short hairs.