Exkurs: Die späte Rehabilitation Schmidts

I see that this term has been discussed to some extent already, but this occurs as a sub-heading in a biographical snippet about someone else... Thus it is logically a digression...

But digression has a negative feel to it to me in the sense that it is often used when talking about one thing and then changing the subject mid-stream, realizing that you're going off on a tangent that you didn't mean to go on, and saying "but I digress" to pull yourself back.

Excursus looks like it should fit, but I've never seen it used anywhere (that I recall)... Anyone use it or read it before?