azalea, yes good strategy (think I got carried away with EME). I think it is good to be prudent, especially on expectations, however 1tcf of gas at $100 / 1,000 cu m (we're in Germany here) with 50% tax gives circa £800m. If you then took another 50% off in costs, overheads, etc etc you get £400m which is 40 times the market capital of EME right now. Discounting the sp for risk etc you could be looking at a sp of 10 times its current level for 1tcf.
(Please let me know if I have missed any major costs out of the equation).