Howard perhaps I misread your post, you said the risk is whether they do or don't find oil.
I agree partially, but the risk is muchhhhh muccch more than that imho . They could find oil and have crummy management, or they could find it and have great management. They can have accretive or dilutive acquisitions and they could buy with $ or shares. It is still a very mixed bag.
So the best most of us can do is to use the Sec filings as a valuable source of info, and gather all other info we can. It would be great for instance to meet the managment, however I think it is safe to say most of us never will.
In any case detailed DD is a much better basis to buy on than a total vacuum of knowledge, but it is not a guarantee of success. I will grant that DD is not perfect most times so you have to inject your investing experience and still keep your fingers crossed, but it is better than just keeping your fingers crossed , in my opinion any