If a professional said that, I'd just think he got his degree from a cereal box. I'm a woman, who was unfortunately born male, so by definition I'm transgender. Its just the simple English definition of the word. The M on my birth certificate proves without question that I'm transgender.
Now on the other hand, if this professional were saying that I'm a male and not a female, then I'd be insulted--just as insulted as any other woman would be.