Both the Omni and the Lotus pictured here display some incredible properties of carbon fibre. Have a look at the incredibly small clearance between tyre and frame and then note that neither of these bikes have a seatstay supporting the chainstay. The chainstays are both pure cantilevers, yet, they are stiff enough to prevent the back wheel moving up and down.
I once experienced this first hand when I had to saw up a carbon Bianchi frame for warrantee purposes. The practice is to remove the BB by hacksaw and send the photo to the distributor to satisfy them the frame has been destroyed. I fooled around a bit and removed the seatstays and then attmpted to break the chainstays off by sitting on the frame (no wheels) and leaning back. Eventually everyone in the workshop was bouncing on it but no go. The trick was then to ask unsuspecting customers to try and break it off. Eventually the hacksaw did the trick. I turned the head tube with its nice head badge into a toothbrush cup but the boss in the household didn't think it was classy enough for our bathroom.It then became a pencil holder in the workshop.