>That's just another simpleton-ish tautology as it only restates the assertion that phase-2 trials do not predict phase-3 trials well without any explanation of the cause.<
You could not possibly be more wrong. The “cause” is variation relative to the underlying efficacy during phase-2 combined with selective attrition as programs advance from phase-2 to phase-3.
Most people don’t have much trouble understanding this. I’m sorry that you evidently do.