Almost all B2B sales are lost and won because of people. That's why the best sales organizations hire and retain the best even at a premium. To be the best sales engineers you not only have to be knowledgeable in your customer's business but also have enough social etiquette so that your prospects actually like you as a person.
While, we can treat our LinkedIn profile like a dating profile and list all the reasons why a person should trust us, that initial meeting and its human interaction will determine whether there is a professional fit. I stumbled across this article on "How to Look Smarter" on WSJ which should give almost everyone an "intellectual" edge in that first meeting.