Yeah, good idea. Note that for quiters, this wouldn't work. For most bags, the lower section has less down than the upper section. A continuous baffle allows the user to shift down around. But, the lower section typically has about 1/2 the amount of down as the upper section. At least my Marmot, EMS, and WM do. Maybe that's from use, too. I really never noticed till later.
Note than corrogated pads do about the same, if you use them with corrugations up. Perhaps An asymetric air baffling of different sized baffles in a pad night work nearly as well as open holes, like the Klymit (a good pad, but not really suitable for hard surfaces. 'Corse, neither are CCF pads.)
I believe Franco posted on this about a year ago. Note that in most cases, the higher lofting down is likely too fragile to really overcome the tension of the shell. Lower lofts, say 600, would do better by providing less compressibility.
A brief thought of the system involved gives me this system. A bag with high lofting EN800 fill upper, with lower lofting, EN600 fill, lower. When coupled with the loft pockets, I would expect some improvement from a cheaper bag. Perhaps a continueous film lower body with a Klymit like body mapping upper section would do better than the current Inertia design. Allowing a continuous vapor barier at the ground and a more solid pad design, coupled with loft pockets. Just a thought.