To add to that smack, identifying the actual expected cash flows...

To add to that smack, identifying the actual expected cash flows from their production allows you to specify the minimum share price.

I'm not specifying we should obtain a "true" estimate of the SP because that would be stupid with ridiculous assumptions, i just though it would be very practical to place estimates on the value attained from production. These present values estimates place a resistance value on the SP, which we know it cannot go below - thus placing a safety net on our investment.