Without having seen one of these machines, I'm highly skeptical of the "dust falls to the bottom" theory. I've seen the failure of this idea in other products. The Hoover WT2 bagless, several versions of the Hoover cyclonic filtration system, Bissell Healthy Home, etc.
Dust doesn't always behave in predictable patterns. Moisture content in the ambient air will cause it to stick. Some materials are sticky by nature, say for example, spices. Yes, consumers do vacuum up spilled curry, cinnamon, etc. Then in the absence of moisture in the air, the effect of static electricity comes into play. All the while, there is the force of vacuum at work.
As has been previously voiced above, I have yet to see one of these cyclonic baffles that disassembled anything like easily. I also have yet to see one of these that was even close to clean after use. Thus the requirement for disassembly.