Can you really leverage sales questions to demonstrate your expertise? Absolutely. And, it's one of the best ways I know to show that you're a smart, savvy seller who could bring value to a relationship.
The way you do it is by wrapping the question with your knowledge. For example, I could ask a potential prospect, "What kinds of problems are your salespeople facing today?" It's a nice open-ended question and might get someone talking.
Or, I could say this:
"Based on my work with a number of other business-to-business sales forces, I find that the top three issues they're facing are:
1) Difficulty setting up initial meetings with key decision makers;
2) Getting customers to decide to change from the status quo; and
3) Differentiating themselves from the competition.
Which of these is having the most impact on your sales force?"
See the difference? In the first one, I just asked a decent question. In the second one, I used my knowledge of what other similar customers are facing to set up the question. Plus I asked a more pointed question --- one that will get me better answers. And finally, it showed that I worked a lot with people like him.
You have expertise too. Think about how you can leverage it to ask 3-5 really insightful, provocative sales questions. I promise you it'll have an impact.