You're probably right that your postman isn't interested. But what if your postman is a drinking buddy, or a relative? Or if the letter refers instead to contraception or abortion, and is sent to a young woman who lives with her religiously-repressive parents? In response to Ian's comment: Four line feeds might result in a small percentage of letters going on to an extra page. For an organisation as vast as the NHS, a small percentage can still mean a big cost, both financial and environmental.