The same rule can be applied even if you aren’t using advertising in your marketing mix, and just sales. With sales, you have to keep in mind who you’re talking to and how far up the chain of final decision making they are at. If you are making a first introduction, have something with you that you can leave behind so that if you aren’t talking to the final decision maker, that person has the info they need to easily explain your product. And this kind of person can have a range of knowledge of your product already. If you don’t know their level yet, you have to give them a little bit more than what they think they might need. If you know they have a solid foundation of knowledge, give them a little bit more technical background so they can feel a bit more “in the know.”
And if you are talking to the final decision maker, still make sure you leave them with enough info so that if they have to justify it to someone else, or just talk about it knowledgeably, they then have the ability to do so.