What is the reasoning for the soil left down at the bottom? Is there a flaw in the chemistry that doesn't allow the encap down to the bottom of the fibers? If you pre vacuum the carpet 80% of the soil should be removed. The remaining 20% should be touched by the encap by either the
crb scrubbing the carpet or the bonnets describing/wiping the dirt away. Then there is the post vacuum that should take away the remainder. Now I can see if the full process isn't being followed that there would be significant soil remaining. But if the process is followed correctly what specifically is the shortcoming?