I think that having 2 separate lines that are essentially not associated in any way, except that the fashion line references the original, heritage, line, is usually a winning strategy. Of course, the devil is in the details, but it seems that every brand, be it heritage or sports, that has successfully made an entry into the fashion market without sacrificing its base, has taken this strategy. Nike, of course, is a great example. The way to do this most economically, but also with the least upside, is in licensing.
On a much cooler note, check out the beginnings of my MTO service boots, which are in a special "heather grey" leather, roughout, with the smooth side out on the heel counter. They will sit on a double leather midsole and a beige Vibram 2060 sole. I designed them specifically as "sneaker boots". If enough people want something like that, we can get them in the Styleforummarket MTO program. We will document the entire process.
Right now, I am planning a scout or service boots on a leather or Dainite sole, a pair of oxfords on the same, and a pair of chukkas on a Vibram sole. You guys would vote on the details so that we get something awesome. And it would be malleable. If people wanted 2 different pairs of boots, and there was less interest in the oxfords, we'd do that, etc... What do you guys think?