Yes, I understand this. Maybe it ia just hype (AKA, marketing, but Thinsulate claims to be made up of thinner fibers, therefore trapping more air in a thinner overall thickness than down or other synthetics. Google Thinsulate to find THEIR claims on how R values compare.
That said, I prefer down to synthetics for most applications, but I may make a Thinsulate underquilt with a poncho/tunic conversion. This may be a better choice to wear under my pack as I hike than fragile down.