NWEs LD Gas - potential worth

Here's some numbers for NWE Ive been saving for the right time. Maybe a bit premature, but its an eye opener.

This is for NWE's share. Its LD/NED only. Gas and condensate. No oil.
Assuming AUD15/MSCF pricing for gas, (average price - some will be domestic rate, some will be export rate), and AUD 80/bbl for the condensate.
20M capex NWE's share for 4 wells
50M capex NWE's share for gas processing plant and pipeline.
Total production per day 300 MMSCF. NWE share 60 MM SCF/day
I might have missed something. Ive not been fancy with LT pricing and Ive assumed equity funding. And it is a very simplistic model, intended for ball park illustrative purposes only.

Gives a potential NPV for LD/NED of around AUD 4 billion...NWE's share. Current NWE MC AUD 250 million.

So the question is how much risk is there in the project???...enough to discount it by 95% of its theoretical/potential NPV?? I don't think so.
Is it 25%($1B)? 50% ($2B)? or is it 75% ($3B)? It all depends on what stage of the de-risking journey we are looking at.
If you're blown away at these numbers, spare a thought for the poor old min folk who picked 80% up for $15M, after having failed with a $500M bid for Waitsia. Talk about bargain of the century.
So when I see people throwing SP numbers around...I go back to this and say to myself...do they really know what they're talking about? And this is for LD/NED only. If the other prospects/leads come in...it just adds to the tally.
To my mind, the penny has not really dropped...or has it??(for some). DYOR.