An excellent post on copy blogger: hardly anyone reads/believes a customer testimonial. They all sound the same, they use sugary language and buzz words, they are one sided.
Most sales presentations have the customary slide with customer quotes in text bubbles inside:
  • Far too much text
  • Stuffed with generic adjectives
  • No specifics related to the customer situation
  • Not a specific source who said it
  • No facts, numbers
Do not send a blank piece of paper to your customer and ask "write something nice", instead, interview the customer, write down a very specific story with facts and have her approve it. The "reverse testimonial" suggested by copy blogger is a powerful structuring technique.