I am moving from a bike to a bent trike for the usual reasons - comfort, stability, and so on. I have not decided what brand or model. The Terras appeal to me because they are well made and do not cost 3 mortgage payments.
Yes, I will use the trike without the dogs. I would not run more than 3 dogs. Multi-dog teams train with very heavy 4-wheel carts or ATVs. This is not racing. Think of it as jogging. Attaching the dogs to the sides in "Springer" harnesses just won't work - they are trained to be in front.
The issues with dogs in front are:
1. Hitch point must not interfere with pedals or wheels.
2. Line of pull is preferably below the center of gravity
3. Hitch point must manage some lateral pull. Booms bent to the side are not pretty.
I trained two of our young Siberians to pull a bicycle. Bikes are generally considered the worst for this purpose, bordering on the insane because it is difficult to bail out if they cannot resist a rabbit. When you do dog teams, you learn to bail. On any combination of wheels or runners. I wear a helmet, knee pads, gloves, and anything else I can find in the closet. On a trike I would still wear the full kit. Now I would like to add our Malamute as a wheel dog, which means he is closest to the wheels and almost as smart as one.
The tug line could be attached several places.
1. hooked up at the cruciform, with a vertical pole down from the boom to guide it below the pedals
2. There could be a boom extension past the pedals - could be straight out or down.
So, given those constraints, which of the Terras might work well for my little team?