lol, neither of you can prove either theory. What I believe is not the issue, what has been proven is. I've yet to see before and after waveforms that prove 'burn-in'. Not even once. You'd think in decades of hifi hobbyists, somebody would've been able to prove this? They never have, they always end up falling back on the "my ears are more sensitive than any measuring device", and that is why it can't be proved. lol.
Myths like that sell alot of overspecced hardware, keep propagating them. :-)