I know why that word can't be used but I never really thought of it used in that context as derogatory to anyone. I always felt that was a word that has several meanings. It's the problem we always face in needing to keep up with the people who use terms as pejorative. Just look at this history of words used to describe the cognitively disabled, as discussed above. Initially, certain terms have no ill-will attached to them and are simply a label. Then people find ways to use them as an insult, and we have to change our terminology to differentiate ourselves from those who use the term to mean something bad. Many derogatory terms were once innocent, but then became insulting. "Negro", for example, was once a term that had far more dignity and respect attached to it when compared to the other term people used to express hatred. Then that term itself was used in a disrespectful way, and for us decent people to differentiate ourselves, we switched to using African-American. What is respectful at one point will eventually become pejorative. We'll one day look back at the current era with disbelief that we ever used the term "handicapped". It's inconvenient for those who mean absolutely no harm, but jerks will always "ruin" our vocabulary and out of respect we need to change the words we use.