Why would the mention of a goat's tounge have struck fear into the hearts of medieval prisoners?

Goat's tongue was a form of torture in which a person’s feet were dipped in a salt solution, and a goat was brought in to lick the solution off. The goat's rough tongue quickly caused abrasion and severe pain, and could lick the feet until the bones were exposed.

https://en.wikipedia.org/wiki/Tickle_torture

http://www.questia.com/googleScholar.qst;jsessionid=MtmGC9gDZfTTGC6vtybkSqkkrlFfy8WGL2VfxQTdgjJXd0LjP8yP!427202863!1380883283?docId=5000643484

Artistic representations might attempt to erase the brutality and abuse, but they can never be wholly successful, because we have the power of imagination. We can imagine what it must be like, for example, to experience a torture called the “goat's tongue.” The victims' legs were tied to a tree, and the soles of their feet were moistened with salt water. A tethered, thirsty goat would then lick their feet until the flesh was worn away.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1120948/