I simply think use of the title "Dr" should be inconformance with the cultural setting. For example, an attorney also has a doctorate. It is customary to use the title in an academic setting but not in any other setting that I can think of. Matter of fact, in court the title is Ms, Mrs., Counsel or whatever, but not Dr.

In my corporation's culture where the MDs and all but one Ph.D do not use their title when introducing themselves, it is presumptious for this one and only Ph.D to use his. For heaven's sake, I know Ph.Ds who drive trucks for a living because they decided they liked the open road better. Can you imagine what would happen if they introduced themselves as Dr So and So?

If I meet someone in a casual setting, for instance at a bike club ride, it tells me a lot about a person if he or she introduces themselves as Dr. So and So rather than just a first and last name; the fact that they have earned a doctorate has no bearing on our mutual participation in cycling. If I met the same person in his or her professional capacity and the culture of that industry or business was to use the title, it is absolutely appropriate.