Which is why I've always believed that Air weaves have to do with the alignment of molecules.

I think an Air weave aligns all the available air molecules in an area, in essence making the barrier solid. By changing the angle of the molecules you can alter the refraction of the molecules and thus the opacity.

I think this is why moving an object with an Air weave is one of the hardest things to do in channeling. The weave will solidify everything between you and the object, but it won't help bring it to you. This is why I think that bringing an object towards yourself is done by creating pillars of air below the object and slowly moving it towards yourself. For this reason it is easier to lift something up - until you reach the limit of your ability i.e. the amount of air you can solidify into a pillar (as seen by both Siuan and Egwene), but to move it towards you is a more complex process.

Of course, I think all the flows work like that, well Earth, Air and Water anyway - they consolidate their parent elements. Fire and Spirit are probably pure energy from different dimensions... Fire from the physical world, Spirit from the spiritual one.