Briguy...
I most heartily disagree with your opinion of the effectiveness of Host, when PROPERLY applied. Carpet fiber is synthetic, it cannot absorb water. What happens when you spray a dirty wall with a water based cleaner? It collects on the wall until gravity overcomes surface tension, and it runs down. Carpet has many, many times the vertical surface as it does flat horizontal surface composed of the tips of the fiber. An ultra low-volume carpet cleaning head will spray .5 gal/min, or approximately 1 oz/min the trigger is depressed. An extremely high extraction rate of recovery is 90% ANY water that touches the backing of the carpet begins to compromise the glue that binds the primary and secondary backings together.
The Host wipes the fiber from bottom to top, because there are two 5" diameter counter-rotating brushes. The proper application covers the entire fiber from bottom to top. You can see the compound turn from rusty gold to light gold/grey or even black, depending on how dirty the carpet is. Once a carpet is wet with extraction, you cannot tell for certain if it is really clean, or if the water remaining is masking stains/high traffic areas. With the Host, once it is dry and vacuumed away you can simply repeat the application. On really stubborn/dirty areas you can 'pancake' the spot with the Host compound and leave it overnight. I have removed dried water-base varnish with this method. The application of Host can be repeated four times before maximum effectiveness has been reached. The Host method uses approximately 1 teaspoon of liquid per square foot, or one tablespoon per square yard.
Host can be walked on during application and drying without damage to the carpet. It does not pose a danger of slipping on adjacent hard surface floor. It can be used to control dirt in high traffic areas to keep them from spreading. It can be used to spot clean, even in areas where people allergic to cleaning chemicals are present.
Host leaves the carpet toe-scrunching fluffy, and cleaner longer than extraction because it does not dilute the dirt, only to wick back once the humidity in the room is low enough for the water in the carpet to wick up.
Host really shines as a maintenance process. Once the carpet is thoroughly clean, regular maintenance with Host eliminates the need for any other supplemental or interim carpet cleaning process ever.
The comparison to carpet cleaning and clothes washing is inaccurate. Shirts, jeans, sheets, etc are woven cloth that require water flowing completely through the weave to get truly clean. A lot of water is used up to remove a comparatively small amount of dirt. A more accurate comparison is how we clean garments like outer coats, suits, sport coats, tailored dresses. Why? Because these garments have structure built-in that precludes being saturated with water and tumbled. These garments are treated gently. They are saturated, but with fast-drying chemicals, much less water.
If you look on the Host website, there are articles about school systems, casinos, hotels and health-care facilities switching entirely to Host carpet cleaning systems and methods. There is almost no downtime, the maintenance is on-going and eliminates concerns about over wetting and drying times. The company continues to grow. I know of no other system that preserves the life of carpet for over three decades if properly and regularly used.
1) Only 100 sq ft can be covered at one time (500 in open commercial applications) 2) the more brushing, the better it works
I have accomplished amazing results with every carpet cleaning method there is. A lot of is is time and patience, not being in a hurry, attention to detail, and the equipment. But the best, longest lasting results are with Host.