Hi Dave,
Your video is really good.
You need to work on your wand technique at little. As has been pointed out, you never lift it off the carpet to allow the lines to clear of moisture so never get the true potential of your system, also you leave those horrible wand marks in it which even when you brushed it post cleaning they were still present in the background and that spoils the overall effect and can be the cause of complaints. A straight-forward and then straight back pass over the same area both with the trigger pressed and then move across two thirds of a wand width (so that each pass overlaps the last one) and the same again until you've covered say 8 feet. Then go back over the area starting at the beginning of the pass pushing forward from the beginning of the last pass this time without pressing the trigger just to dry the carpet and lift the wand at the end of each pass then start a new one. This sends the carpet in one direction without zig-zags being left. And when you brush the carpet, do it with the pile, not across it and you should completely remove any wand marks.
It's all a learning curve, mate, and I like your professional attitude.
Simon