Dan, stimulation of oil wells is quite common, particularly steam injection. The oil is still there; it just becomes harder to recover. Oilfields in Saudi were so easy to recover back in the day that all they had to do was sink a hole and perforate; now they'll have to pay a little more to get it out of the ground and their disposable take on the energy $ will go down - their costs will come more in line to what it takes to produce a barrell of oil domestically. You should see the wells in California; I have personally logged two different wells 20 feet apart (the oil is highly viscous and does not migrate through the rock well).
Yup.
The phenomenon is easy to grasp with a couple of easy analogies.
Imagine someone in a hot air balloon dumps a bag of $100 bills over your house and you get to keep all that money.
You would pick up the bills that are nearest to you on the ground as they would require the least amount of effort to get, and then you would work your way around to the stuff on top of your car, then get up on a ladder and get up on the roof and up in any trees. The stuff that takes the least amount of effort gets picked up first, then you will gather the stuff that is harder to reach after you can't find any easy stuff.
The same is true for oil exploration and exploitation on the part of our oil-using civilization. We picked up the cheap, easy to get stuff and it is running out.
Now imagine that you are a person trapped on a deserted island. You need 2000 calories to live and the only food on the island is in the form of some fruit trees in the middle of the island that drop fruit regularly on the ground. You can walk over, pick up and eat a fruit at a cost of say, 10 calories, and get 500 calories from each fruit.
You will need 4 fruits (plus a very small fraction) to survive per day.
Now imagine that the easy fruit on the ground is gone, and you have to climb up the tree, go out onto a branch and laboriously saw the fruit off the tree. This takes 200 calories for EACH fruit.
You will now need 6.67 fruits per day to survive and your total caloric intake has gone from 2040 calories to over 3300. Your body still only needs 2000 calories, but you had to spend 1300 calories to get that.
The same is true for oil energy. The "return" on each new barrel of oil gets slimmer, so even if the world's economy/energy needs weren't growing our energy consumption would.
BUT
The world economy is growing. For each 1 percent of GDP growth, we need 1 percent PLUS X percent with the X percent being determined by the efficiency of our energy sources.
SOOOO....
If supply is constant or shrinking, and overall demand is going up, where does the "price point" go?
You guessed it, UP.
High enough that competing energy sources will eventually become more cost-efficient. I think faster than the oil companies expect.