Derek insists that his interlocutors MUST provide numbers, maths and physics while he has no such counter obligation.
Fairly common ploy. The claimant tries to suggest that the only rebuttals that are dispositive of his claim are those that critics are either unqualified to produce or unwilling to take an extreme effort to produce. This doesn't have to be scientific knowledge. The "reasonable" (but impractical) rebuttal can also, for example, require distant travel or considerable expense. Common inducements include, as we've seen here, appeals to flattery: "I heard you guys were really smart and professional." One can also attempt less directed but equally persuasive options, e.g., "How can you be so sure of your objection unless you've done the required work?"
Obviously when the claimant provides no substance on its own, this amounts to reversing the burden of proof. It advances the hidden premise that any objection a critic has is presumed to be ill-founded. It's a close cousin of the
ignoratio elenchi fallacy to suggest that only one of several possible refutations is allowed. If, hypothetically, a claimant simultaneously commits an error of inference and also supplies a speculative premise, either one is fatal to his claim. He doesn't get to escape that by demanding an exhaustive refutation of the premise when the claim fails much more easily and straightforwardly by a faulty inferential structure. Further, on the off-chance that a critic supplies a detailed technical proof, such proofs often provide enough crevices and toeholds for a persistent claimant to keep up the demand, handwavingly insisting that more and more rigor be supplied regardless of its ability to affect the outcome. That's why the simplest rebuttals are also the best rebuttals, regardless of what the claimant prefers. Finally, it's hard to imagine what someone is supposed to do with a detailed scientific treatise in fields he has already said he isn't an expert in. If the core problem is that the claimant doesn't understand fluid dynamics, providing an exhaustively considered analysis in fluid dynamics won't fix that. Demanding explanations one can't actually use rather tips the hand to show it's just a rhetorical ploy instead of a genuine request.