He retired from his optometry practice in 1980 (25 years ago). He's published Financial Insights since 1995. I have also worked more than one job during my working career and find that to be quite normal. Why do you have a problem with that?
Just a thing about titles, I suppose . . . especially when they have no bearing on the subject matter. What's interesting is that, as a doctor of medicine (if that's what he truly is), he should understand that simple fact.