I know all about dipole...u/h frame, ripole..ECT. it takes a lot of displacement to do 35hz properly. What your stating is correct, doesn't load / pressurize the roomShould behave somewhat similar to open-baffle dipole subs, room position is key to achieve even bass response. They interact differently with room modes then non-dipole designs. When setup correctly, an open baffle sub can create a qualitative superior low-end experience compared to regular subs. But, not everyone likes this type of sound, e.g. it doesn't provide the "impact" a regular quality sub is able to deliver. They're two different worlds.
I'd still like to see the "planar" that can do that.
I remain optimistic.