You can see a video clip and read more about his book, Getting Naked, here. Back to his BW piece, where Lencioni says that naked consultants:
...do no real selling at all, foregoing that activity in order to find a way to help a potential client even if the business never actually becomes a real, paying one.
What does this have to do with marketing? Everything: In an ideal world, customers want and expect marketing and marketers to be naked. They want to know the real benefits of a good or service, they want to know the real price, and they want to know when an offering is not right for them.
It takes courage for a marketer to be naked in front of customers (and competitors) but ultimately, it does build trust and loyalty. This is all about the long term, not just a single transaction. Customers resent obfuscation and crave transparency.
Here's a perspective on naked marketing based on the decades-old rhetorical question, "Would Macy's Tell Gimbel's?" The two department stores were archrivals situated across the street from each other in New York City's busiest retail district. It was a point of competitive pride not to reveal info that would send a customer to the rival.
However, as this blogger points out, Amazon routinely lets transparency rule by listing all sellers of a particular product and showing their offers in price order. Now that's naked marketing--being confident enough to put the customer's needs first. I know Amazon gets a cut of the sale when customers buy from one of its sellers...but it still takes a competent, confident marketer to allow customers to make that decision on their own.