I have an Aeropost that got stuck after I used my 2014 Giant Defy Advanced Carbon Fibre bike to commute (bike had to be stored in a cage outside during workday... in Canada therefore Fall temp btwn 1-10 degress).
The seat post is an Aero (tear drop shape) in a carbon frame.
Had been stuck for three years, but with a combination of Carbomove AND using this reversible clamp as a spread I was able to finally remove the seat post.
Technique involved spraying with Carbomove for a few days then, when the clamp arrived, using it as a spreader from the bottom bracket to the front of the seatpost... After a handful of squeezes on the clamp to apply outward pressure, the seat post popped out.
I called 15 otherwise really reputable bike shops and they all said it would be over $100 and may not get it out anyway. Oh and it may break your frame and almost certainly will ruin your seatpost...
Hope this helps others in the same spot.
Cheers.