Roger,
No matter how hard I try, I still frequently say "Bay-tiss" (and Cal-i-bay-tiss). It's hard to break a habit of so many years. There is also the problem of being misunderstood. When I was at Boeing, I worked for some years in the Engineering Liaison organization. At Boeing, the most common pronunciation of liaison is something like "lye'-a-zun", and when I would answer the phone "engineering lee-ay'-zawn" I was usually greeted by a long silence from the other end of the line while the caller processed the unfamiliar pronunciation.