The responses are hilarious. Well they would be if it wasn't such a cluster fuck of "known knowns, known unknowns and unknown unknowns" (never in a million years thought I would find cause to quote Rumsfeld when sober).
It's a bit like a pub argument with the bloke who bought a Rolex in the market for £50 and simply wont accept it's a fake. The more unsure they feel on the inside, the nastier their tone and more strident in support of its intrinsic unalloyed genuineness they get. And then they stop wearing it and forbid all further discussion. Often with threats of violence.