Reading Buhner's book, it does not seem to me that the Fogg was what did the fermentation, rather it was some kind of psychotropic moss-type thing. If I am reading it right the moss coexists with wild yeasts on the heather plants. As the ingredients are not cheap I would hesitate to rely on wild yeasts to produce a good tasting mead.
I have a recipe similar to yours that I was going to try out too. I have a small jar of heather honey ($12 for 340 grams!) but I don't plan to use the whole thing because it has such a powerful flavor and aroma. I thought I might hit up the local bee keeper for a piece of brood comb to put in there too.
I made a tincture of propolis a couple years back and when I added 20 ml to the gallon of mead all the resins and waxes came out of solution to make a big cloud that I had to clear out after about 2 years with some chitosan.
I did make an all-heather honey/heather blossom mead that cost me $40 a gallon. It is still aging but the aroma of an empty glass that held the mead will fill the room for days afterward. I also make a liqueur with 52.5% heather mead, 10% heather honey and 37.5% scotch whisky. Excellent!