About 2 editions of 'African Hunter' later, Don Heath changed his mind a bit about the Model 70 safety being on the 'wrong' side. I think Cooper may have done a bit of chest-poking over the phone, Heath mentioned the fact that Cooper and others lie their thumb along the RHS of the grip, rather than wrapping their thumb over the grip, and that in that case the normal right-hand safety is entirely appropriate. If you need more details, I could have a go at finding the article...

It didn't change my views though. I'm right-handed, and when approaching game with the rifle at either 'port arms' or mounted, my thumb is over the top of the wrist. For me, the safety must be on the top-tang or the left-hand side of the cocking piece for quick operation.