As FullWings says, the measure of 'insufficient fuel' 'too less as possible fuel' to paraphrase is when aircraft are regularly tech stopping or diverting due to lack of fuel, and believe me, management and the beanos would soon notice and I'm sure things would change. The number of regular fuel 'emergencies' should be a guide to the wisdom of current policy.
I would hope any pilots+ Ops Staff with an interest in Fuel Planning in the 21st century might visit my tech log thread on fuel planning.
I have an in-built resistance to SCF since I think it is contrary to the 'traditional' intention of CF, but am happy to accept a statistical 'extra fuel' added on a CFP for 'expected' ATC delays at destination.
Is it time to look at changing our planning system to reflect the vastly improved information available to crews and ops both pre-flight and en-route?