Ah, thanks everyone, this is making sense to me now!
I've noticed Fender, Warmoth, Musicman and others offering roasted bodies and necks, and I'm prepared to accept that hallowed names such as these wouldn't waste research time and money on snake oil.
I also think I've read somewhere in the past that you could 'loosen up' the soundboard of an acoustic guitar and improve it's sound by placing it on top of a speaker and subjecting it to the vibrations, I suppose this is the same concept of quickly introducing the kind of vibrations it would naturally be subjected to over hours of playing
The only thing which makes me slightly sceptical of these kind of claims though, is that manufacturers never seem to back up these claims with some sort of definitive A/B test of treated and non treated products, which would clearly show us the benefits, which seem subtle to my cloth ears, and that often all I can find is the testimonial of someone who has paid (a lot of money) for an instrument or part of one, and would, quite understandably, like to think it was worth the cost and an improvement on a stock item