We're getting more efficient at well placement, yes, and this does cut costs. As far as secondary and tertiary recovery, that's another story. In general, we only get about a quarter to a fifth of the oil out of the oil-bearing rock. You can start really pushing recovery costs up when you start pumping significant amounts of gas or saltwater down there to try push remaining oil out. One thing that works is CO2 as it's soluble in oil and "swells" the droplets and thins their viscosity, allowing them to be pushed better. The economics of these things are rather worse than you might think, though, as they consume immense amounts of energy to perform.
I suppose that it's a common misconception that engineering a better mousetrap is all it takes to make the economics of pulling oil out of rocks work. It does to a point--but it takes real energy to push a highly viscous fluid through those same rocks and that can be a horrific drain on the economics of the endeavor. We've even gone so far as to set fire to a portion of the field and pump air down there to keep the fire burning to provide heat, CO2 and pressure. Fire inside rock, of course, isn't anything like what you'd normally imagine it to be. Imagine trying to control that for a huge area underground... Take Gwahar, for instance, ...almost a couple hundred miles long and about 25 miles wide, 1,300 feet thick. At its peak, it was providing about 5.5 million barrels per day. It's watering out now and they're cycling A LOT of water through it trying to get out the last drops. Chances are it's going to go bigtime due to the nature of the recovery methods used. We'll lose about 4.5 mbpd production within the space of a year or two.
No, the real problem IS that the actual effort to get the remaining stuff out of the ground requires REAL energy. When your production base is in decline and, worse, requires exponentially greater energy inputs to MAINTAIN said production AND your economy REQUIRES exponentially greater energy inputs to pay off EXPONENTIALLY INCREASING debt... well, h*ll... you're in real trouble, plain and simple.
Crap, you don't think that silly little price spike in energy costs last year was a complete fluke, didja'? The forward predictions of Peak Oil theorists very presciently predicted years ago that that's exactly what would happen, including the demand destruction that would ultimately and paradoxically drop the price to such lows for awhile. Horrific volatility. Nobody, and I mean nobody, wants to see this come true. And if you disregard what the optimistic pundits are saying and focus on the arcane data, predictions and geopolitical posturings of the major players, you'll see the handwriting on the wall.