Jonas Kaufmann on German TV via YouTube reveals that he began as a mathematics student. His career started in Saarbruecken. "Wenn man von Fach zu Fach springt...." This describes Jonas's career--springing from Fach to Fach--"sometimes light, sometimes heavier, sometimes with coloratura, then the voice can't really develop right. When one can't concentrate, everything comes out a little not right." Let's hope he has found his niche. [Translation is approximate.]
A native Muenchener, he lives in Zurich--a lovely city that I enjoy more each time I visit it--with his three children, all of whom gladly play instruments, the oldest flute and piano, the middle one started on violin and now plays trumpet. The youngest likes anything that makes a lot of noise.
Commentary: I still see Jonas as a Heldentenor, something I'm not sure he sees. But being a Heldentenor is basically two things: tone and learning to sing consistently large. It requires focus.