Daniel Ehrenberg wrote:
I have recently been tempted to wipe most of that article's talk page and leave only discussion about the article itself, and add a big notice saying "WIKIPEDIA IS NOT THE PLACE FOR YOUR OWN THEORIES".
I think wiping talk pages is against Wikipedia policy unless they're copyvios,
*refactoring* talk pages is ok -- cleaning up and summarizing. I think removing swathes of discussion that is not relevant to the article would be a good idea. Having it there shows other crackpots they're welcome.