I also have wanted to learn this cast-on but haven't been in love with any of Cat's books I've looked at so far, although it could have been just because I was cranky about feeling like I HAD to buy another book. Interestingly, though, when Interwave had their hurt sale, I looked up one of her books they had available for more info and found this review (excerpt, full review here):
There's been a lot of buzz about the Moebius Cast On, this is what finally motivated me to buy this book. I was stunned to realize that this "special" cast on is nothing more than the invisible cast on worked with the circular needle's coil serving as the waste "yarn". My irritation stemmed in part from the fact that I used this technique for casting on a moebius scarf when this scarf first appeared on the web as a free pattern back in 1995 or 1996. The invisible cast on is in Mary Thomas's Knitting Book which was first published in the 1930s. Finally, Ms Bordhi gives credit to no one. Not to the originator of using a moebius as a knitted entity(Elizabeth Zimmermann) or to the originator of the moebius knitted from the center out.
I don't know if there is any truth in that quote at all, just found it interesting myself, but i think the 2nd method here is the "original" moebius cast-on mentioned in the review and sounds like what Diane was explaining too. It did make more sense to me, but I haven't tried it again with this method yet.