"Today, thanks to... Peggy Mathis, a lot less work is needed and the chances of cutting the garment have been greatly reduced by using Peggy's Stitch Eraser. ... the Stitch Eraser is used on the bobbin side of the error first. Stroke the bobbin (area) of the threads to be removed, grinding them away, then remove the colored thread from the reverse side. Large fill areas may take some time, but a lot less than replacing (customer's inventory)."
"One important feature of removing designs from knits with Peggy's Stitch Eraser is to make sure you have used a very stable backing. If you only use tear away or very light backings, there is a chance you will grind right through the shirt and leave a hole too big to patch."
"Repairs and Rescues: New Tricks of the Trade" Gregg Chma, Embroidery Times