Hi Bob...You are correct. My full scale banner tow pilot buddy confirmed that they tow from the tail...and the reason for that is so that if they ever stall the plane, the drag pulling on the tail will help prevent the plane from rapidly going into a spin. A spin could get real messy with a tow line involved.
Towing by the tail does induce a lot of effort which will tend counter some of the turning movement of the airplane.
With the model, I don't anticipate any stall/spin activity, and of course I can dump the banner at any moment.
In full scale banner pick-up...the tow line is connected at the tail, and then is carried aloft with the hook end attached up near the wing struts, to be released when they do their approach. They dont want that hook to be able to reach the wing and prop in the event of a missed hook-up and then the hook snags the ground momentarily then slingshots forward doing some damage to whatever it may hit.
Obviously the tow hook line is quite short....less than one fuselage length. Thats how low they have to fly to hook up with the banner...and then immediately pull up hard. Yes, it is a dangerous job. These guys are a one man show. The pilot first sets up his ground poles which hold the banner tow line. Then he takes off, flys back down low and fast...drops the pick-up hook...hopefully he snags the banner line...then zooms skyward real quick.
And they don't make a lot of money either...mostly relatively new pilots just logging a lot of hours.