Lauxier--Joe is an absolute jewel and a grand fisherman, but I wonder a bit about the scent thing. I was under the impression most fish had little if any sense of smell, with members of the catfish clan being a notable exception. However, I don't know that I've ever read anything scientific on the matter one way or the other. If there is a fisheries biologist out there, please advise.
Having just said this, I do know that one of the major "hardware" fishing companies makes some kind of scented trout bait which is supposed to work very well.