Well it looks like some dogs, at least, like it. Maybe they could be put on a less arduous test ride first, since it’s not possible to ask them in dog language whether they would care for the idea. No Dr. Doolittle is available for that.
Anyhow if it’s supposed to show whether the dog spinners are going to have good luck, why send any dog on the ride more than once, or have more than one spin?
And... they might already have a set of dogs that have been tested and which seem to love it. A nice steak after they’ve dried out and gotten their land legs back might also be an inducement to these canines.