Quick comment - I read the "worth 10's of millions of dollars" to be referring to the amount of cash ERHE would have had to come up with to pay for their "carried" portion of the drilling so far to date. In addition, the more in the future is referring to the continued "carry" until profit oil. For a non-oil company, this truely is worth a lot (IMHO). To think, if all goes well, and it takes 2, 5 or even 10 more years to bring a commercial discovery into full production, the interest alone of the ERHE proportional investment could be worth ten's of millions and more. (also remember that profit oil begins at first production not when a field is brought on to full production)
The carry strategy has been successfully negotiated in blocks 2 - 4. I suspect they will continue with that kind of strategy (giving up a portion of their rights) with other blocks (EEZ & now CHAD) until there is a foreseable cash flow from one of their properties.
Just my take.