A story can make copy far more memorable and persuasive, but only if it stays tightly connected to the actual point you're making.
Use a Real, Specific Example
A believable, detailed story about one customer's situation is more persuasive than a vague, generic scenario.
Keep the Story Proportional to the Point
A long narrative in service of a minor point loses the reader's patience before it earns its payoff.
Land the Connection Explicitly
Don't assume the reader will draw the intended conclusion from the story alone; state clearly how it relates to what you're selling.
Next step: Use the Sales Letter Writer to build a persuasive narrative structure around a real customer story.