In my average day, I will spend a portion of my day dealing with Joe Public, and a portion dealing with doctorate-level types, mostly PharmD and MD. What I mean by Joe Public (or Josephine- lets include both genders) is just a community sample. I'll call it JP. JP can be educated or not, but when I deal with JP, I need to be understood regardless of education, so I speak to JP like I would a twelve year old. I'm not making one of those "most people are stupid" comments, I'm only saying that I don't know who can understand what right off the bat, so I've got to keep it simple. When I speak to the PharmD and MD types, there's a bit of an expectation that I heighten the vernacular a bit. The result is that for half of the day at one level of communication, and half at another.
Lately, I've found myself deliberately dumbing down (yes, I said dumbing down) my conversations with the doctorate crowd. My rationale for this is that most of them tend to explain things to JP in ways that leave JP utterly confused, and I figure if the doctorate gang hears things put more simply than they usually hear them, they may start to explain things to JP a bit better. I think that if you're dealing with a normal, heterogenous sample of the community, you should be expected to communicate at their level, so I'm trying to discourage these guys from continually confusing JP and sending them away uninformed.
In short, yes- I moderate my language to the point where I'm not sure what I would sound like if I just spoke naturally.