Actually there has been a lot of progress in UL, though few apply it to bike touring. The gear really isn't a problem, though you may need custom bags to stow it all aerodynamically. A big bag on a seatpost rack, frame bag, and custom bar bag under clipons should do it fine. Be sure to allow space for a 6-pack of Ensure. Of course you'll need at least 4 tubes, spare tire, cables, lube, multitool, but I never go LD without that stuff anyway. Doesn't weigh much or take up much room. Of course you'd use a carbon bike with aerobars and skinny tires. I don't know about carbon wheels. Deep section low count blade spoke aluminum probably makes more sense. You'll want to train with a Camelbak and bottles to cut the frequency of stops and to be able to bridge the dry spots.
It's not about the gear, it's about you. If you're into breaking some record, then listen up to the RAAM rules. That's why they're there. If you want to fast tour across the country, go in mid-June and sleep when it's dark. You'll have plenty of daylight to push yourself to your limits and that'll cut down on your lighting weight, too.