But ass and bitch are not a good comparison to phrases such as master/slave, which have a rich history in programming and convey meaning that would be difficult

But ass and bitch are not a good comparison to phrases such as master/slave, which have a rich history in programming and convey meaning that would be difficult to replace. Master/slave tells me that an entity controls another entity unconditionally. This is a critical aspect of the relevant relationship, and I know of no other phrase that conveys this meaning nearly so well. Obviously we use the same words to describe a similar relationship between human slaves and masters. There's no rational reason to forbid technically useful and precise language, just because it also describes something else that we don't like.