Interesting thought about reclaiming the word from where I sit. As a trained chef (baker), the verb "retard" is commonly used for its meaning of slowing something down. This is usually with bread making, especially sourdoughs. Yeast development can be retarded using colder environments to enable better flavor and texture. Honestly, I have a loaf of bread retarding in the refrigerator now, and I'll bake it in the morning.
Since I work often with bakers and baking companies (marketing), the word is used often and I've never once heard someone make a crack involving the word's derogatory usage. Yet, I know the word is not one considered acceptable to use to describe a person or one's actions. But how the word is used in my world obscured its obvious position as something ready to be reclaimed.
And it gets stress on the the first syllable where it's used as a noun, second syllable as a verb. cf "address", "attribute". (I do realize the noun–verb distinction doesn't come play in the UK for the former.)
Since I work often with bakers and baking companies (marketing), the word is used often and I've never once heard someone make a crack involving the word's derogatory usage. Yet, I know the word is not one considered acceptable to use to describe a person or one's actions. But how the word is used in my world obscured its obvious position as something ready to be reclaimed.