Chris,
The most important drying stroke you can make is the one where you are spraying water into the carpet. Get the first stroke wrong and all you will be doing is struggleing to rectify a problem you have created.
Think of it this way - water from the jets hits the carpet and 1/2 second later the vacuum slot collects a proportion of the water.
Later, we'll say 6 seconds, you make a drying stroke. What has happened during that 6 seconds? If the water left by the cleaning stroke is more than the pile can hold, it has started its' journey into the backing nad perhaps beyond. The chances of recovering this water has diminished, and with a subsequent drying stroke you are into a situation of deminishing returns.
This is part of the reason for the Belgian Wilton problem - the amount of water that can be held by polypropolene is very small.
I am not saying that a drying stroke is a waste of time, just that except in a flood situation twenty drying strokes will not recover measurably more water than one, and that the cleaning stroke is by far the one where 'wandsmanship' is critical.
John.
PS. An airmover, combined with proper ventilation can make a tremendous difference to the evaporation rate of the water you leave behind. If you've spent the money, get the benefits.
