The exact same testimonial under different names – ouch.
If the testimonial and author were both repeated in the example below, that would look sloppy, but, when the names are different, visitors start to think the worst: are the others real? Is that really a picture of a customer and her daughter?
The best defense is always careful editing at the time of entry, but also looking at your site regularly and catching these problems before they go on too long.
What's Your Take?