John, Good question, I worked for years in a group home for developmentally disabled adults and I saw what you are talking about (patronizing tone) from staff members and visitors. See it at the VA hospital too. I've seen are people who use a one-size-fits-all-baby-talk that is not their normal way of speaking to ALL the "residents". I'm definitely no expert but...Seems to me like it's ok to have fun, and talk about things that are interesting to both people in the conversation, but when the conversation gets forced, that's when the patronizing tone can creep in. I think it's a fine line. When the ability of the person you are communicating with is very poor or almost non-existent you can still communicate. I try to relate in some way, music works great. I always start by talking to someone like I would to any stranger, then I might modify my communication if I feel I need to, know what I mean? I feel the point is to just be conscious that this is a potential problem, I think a lot of people never even think about it.