Mitch,

> "Mr. Smith, would a 20% increase in
> your employee's productivity, in your case a
> potential $2,000,000 annual increase in
> sales, be of interest to you?"

Your on the right track, but your question is closed-ended... Mr. Smith can answer with a blunt "no" and hang up on you. Try this instead:

Mr. Smith, HOW WOULD a 20% increase in your employees' productivity interest you?