Aye, that goes for a lot of these arguments dunnit? One side says "Prove it!" and the other says "Disprove it!" and it ends up as a dialectical Paschendale, because the issue of contention isn't particularly amenable to study.

I'd like to think that with all these subtle, hyper-complex phenomena, that as computing power gets better, and as the relevant data become more linked and available for analysis, that eventually we might be able to get a handle on the weird stuff. It seems that statistical analysis might be one way around the impasse. No proof/disproof as such, but some pretty heavy indicators of the probability of odd stuff happening/not-happening by chance might come in useful.