VLM removes soil as do all carpet cleaning methods.  What I do need convincing on is what they leave behind.
The way I clean with HWE is very similar to washing your clothes.  Wash cycle/Agitation/rinse cycle.  Apply cleaning agent, 
CRB, rinse with water and groom.  With the 
CRB doing most of the work, I can reduce the amount of cleaning agent and water pressure.
So when I clean for a  repeat customer.  At any point, I can remove the hose cuff off my wand and I will see just water inside the hose, extremely little or no white (cleaning agent).
Today I cleaned for a past customer that I used to clean annually.  Last year she tried a VLM cleaner.  She said it looked good at first but then kinda *dulled out*.  When I started cleaning I noticed a slight reduction of suction, so I take off my cuff and see lots of white (cleaning agent)  so much so in fact that from that point on I just presprayed water because there was enough cleaning agent in the carpet from the VLM that I just needed to activate it.
Pictures say a thousand words.  Again, all I presprayed was plain, softened water.
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