Reviving cryopreserved patients does not "bring them back from the dead." It just revives them from stasis. They aren't anymore dead than a mind mid-upload.
Actually reviving the dead is impossible because you wouldn't be able to bring back their soul.
Where "soul" is like "clearly causally connected thread of experience"? Or something else?
http://www.dailycamera.com/boulder-county-news/ci_18282009?source=most_viewed
I'd imagine the efficacy is halfway between proper cryonics and embalming and burying; the more interesting part may be the festival. Nederland is a small town 20 miles from Boulder, CO. I doubt the festival attendees are cryonics advocates, but they don't seem prone to the negative associations corpsicles often raise. Perhaps it's just because Boulder, Colorado is full of weirdos, but I wonder if there are more exploitable effects in play.