My job as a technical consultant to our sales staff is to bridge the gap between needs assessment and salesmanship. I have a 0 tolerance policy about lying during sales (I have to be to keep our sales guys from making false promises), but I struggle with finding that delicate balance between the truth, focusing on what's important to a prospect, and the manner in which you talk about capabilities you don't have. You cannot simply tell a prospect you don't have a feature if they don't actually need it because there's a lot of psychology at play. A competitor told them they needed that feature so you now have to mitigate their concerns. You essentially need to find a way to be truthful while simultaneously transferring emphasis to your selling points or to their needs.