Sean, it is a pity that “you spat the dummy”…when you are being nice you have a great deal to offer this forum.
I believe that the photos posted by cl12pv2s of banner towing in Hong Kong are not of the Skycom system but are those of a competitor.
Contrary to some views expressed on this forum the flying is challenging. Trying to maintain level flight at 22 – 28 kts IAS (perhaps faster depending on the system used) when operating for as much as 3 hours at a time, in or around an urban environment with a 200 ft long line load combination, and not screw up or die from boredom is rather challenging. The airspeed indicators are not that accurate at such low speeds and a small speed change can result in a large power change and not always in the direction you would think.
There are three or four specialist companies in the world producing the banners, and providing technical services, and as long as they have oversight of the operation then I reckon it can be conducted in a safe and efficient manner. What concerns me is when all the ‘wannabes’ start giving it a try!