I should also answer your question "flow rates vs energy...

I should also answer your question "flow rates vs energy content".
Energy content has been covered by my previous post.

Of course, all very well having a mega huge gas resource, but if it trickles out of the ground too slow then you can't produce enough to sell in (say) a twelve month period (annual revenue).

This is where flow rates come in.

Flow rates are how fast the gas is delivered to the pipeline, and hence how quickly the dollar meter ticks over.