I thought this was interesting, having been a salesperson and a psych man by education (which I could be wrong here but you might be as well?). I don't know what industry your trainees were working in, but I have some history in the illustrious world of automobile sales, a place were a sale is a sale whether or not you had to kill someone's children to get it.
What's funny is that your three tenants here, which sound very good, seem to be leading toward a diametrically opposed goal to the training you receive in car sales (which is effective, mind you). From the perspective of my numerous trainers and "mentors", the surefire road to a sale is in making sure that as few of the products qualities come into question as possible, and if they must, they are to come from your mouth or be answers to strategic questions you asked the customer. The reason; people can only become less interested than they must have been when they actually decided to drive to the dealership and talk to someone. Essentially, from this point of view, the "art of the sale" is actually making the sale without the customer being aware of it. As exploitative as it can be, it is actually fascinating to watch and learn from the guys who can do this well. People who barely have high school diplomas, and certainly almost no knowledge of their product, using every psych technique right out of the textbook, doing it on the fly, and delivering it within casual conversation. Random customers, just out to kick some tires on a sunny day to pass the time, never know what hit them until they're shaking hands with the general manager after a test drive that they don't really remember agreeing to.
I'm not sure why this is entirely relevant, just caught my attention. But, it does have to do with sales, and I think what sparked me here was the notion that my type of sale is actually really well suited for a watch. Your type which caters toward the customer's needs, though very honorable, can pretty much only lead to a customer's confusion and disinterest in this market. Why do they "need" a Rolex after it's been explained to them that a Grand Seiko can do just as much for half the money, and what if they can't even understand your reasoning? Probably a better scenario, if one were a career jewelry salesperson, to practice "leading" and other techniques that create sales without all the messy details coming into question. Makes me wonder if there are any out there doing it.